Danish Thoughts on Finnish and Swedish NATO Membership

The article is premature. The Danish Gov­ernment and opposition politicians have not yet decided how they will react to the geo­strategic situation that we face after the Russian­-Ukrainian War has pushed Europe past normality and triggered the member­ ship decisions of Helsinki and Stockholm. In Copenhagen, there is still no formally confirmed understanding of how Denmark’s situation has changed. The politicians post­ pone anything but the most general under­ standing of what the armed forces should try to do hereafter. All seem to wait for a mira­cle before a costly response becomes acute.

Therefore, you can only have my per­sonal essay with analysis and conclusions. However, history does shed some light on the situation, and I shall start by going back to the only period where a formal analysis was conducted with Denmark and South Sweden seen as a geopolitical entity in alli­ ance against a common threat: the 1948–49 Scandinavian Defence Committee discus­ sions. Then the experiences and demands of 1940–45 had brought Sweden, Norway and Denmark closer together and made fu­ ture cooperation natural.1

The discussions then did not result in the Union, but they were followed by forty Cold War years of a discreet, limited and secret cooperation that has been reconstructed by Mikael Holmström.2

There had been agreement that a sea­land­ ing was expected to take place from the south­ ern part of the Sound off the Swedish coast in Faxe and/or Køge Bight(s). Copenhagen was considered vulnerable to aerial bombard­ ment, and enemy use of Swedish air space would make timely warning and effective defence of the city very difficult. However, during the Cold War the Danes did not wor­ ry that Sweden would not cover our flank well enough. In the end, the Danes trusted that the defence of Sweden was rock solid. South Sweden would be effectively defend­ ed against any Warsaw Treaty Organisation (WTO) air, naval and amphibious opera­ tions from their bases on the other side of the Baltic Sea.3 An effective defence meant the ability to last at least as long as our own.

Southern Swedish defence similarly de­ pended on the successful NATO defence of Denmark, but here there was less optimism about the endurance. A Swedish defence plan option covered the situation where Denmark had been lost.4 Direct Swedish assistance was ruled out by Denmark’s NATO mem­ bership. It had been easier to discuss when both states were neutral. In 1933 there had been talks between the Swedish and Danish General Staffs about a possible significant Swedish Army participation in the defence of Zealand against invasion, thereby creat­ ing a forward defence of Southern Sweden.5

Defence integration made possible by a common alliance status: The Scandinavian Defence Committee report

As a response to the worsening international situation in the second half of 1948 and early 1949, the Swedish, Norwegian and Danish leading politicians, militaries and civilian experts discussed a possible defence union. It could either be as a fully neutral block or one aligned to the West.

According to the 15 October 1948 direc­tive for the committee work6, the union would create a common defence framework. However, the Norwegian and Danish armed forces were still very weak. Especially the Danish were in the very early stages of res­ toration, both in material and personnel. A defence union would give a clear organisa­ tional objective and commit the Danish and Norwegian politicians to find the necessary money. At the same time, it would help the Swedes decide in which direction the very substantial Swedish wartime neutrality de­ fence forces should develop and modernise. The common and stronger defence should increase the chances of getting outside assis­ tance if the countries were attacked.

The committee report from January 1949 was thorough and impressive considering the less than a half year available for the work. It started with a short general discussion of the committee’ tasks followed by an analysis of the balance of power between the Soviet Union on one side and the U.S. plus the forc­ es of the newly created European “Western Union” on the other. The Soviet Union had massively superior land forces, the West had a supremacy at sea. The air forces were es­ timated to be numerically similar.

Thereafter the report outlined the current forces of the three Nordic States and went on to identify the threat and possible coop­ eration within eight different war scenarios, where the most important was “Krigsfall DNS”, a Soviet attack against Scandinavia as part of a general East­-West War.

The Soviet objective in an attack on Scandinavia was considered to be the for­ ward movement of its defences, including the air defence, to the Atlantic and the Skagerrak. It would also make it possible to establish of­ fensive naval and air bases there. In Northern Scandinavia the offensive would come direct­ ly from the Murmansk area as well as via Finland against both Norway and Sweden. The Soviet forces might also invade central Sweden from southern Finland and move on­ wards towards southern Norway. However, in the Baltic Sea “a sea and air landing might be limited to Gotland and Bornholm to gain air and naval or even missile bases as well as to flank protection for sea transports, etc, in the eastern and southern part of the Baltic Sea”. Remember this last sentence. It is valid for all east­west or west­east sea communications here.

Southern Norway might be invaded direct­ ly, if Russia could use the Danish Straits as Germany did in April 1940. However, intel­ ligence about preparations should give time for mining the straits and for attacks on the transports by Danish and Swedish air forc­es. Therefore, a Russian invasion of South Norway was likely to come after Russian forces had gained control of Denmark. In the south­west of the Nordic area, Russian sea­air landing could be directed against both Zealand and Scania.

At the start of invasion Russian attacks would be directed against Nordic States air and naval bases, and Russian forces out to try to cut sea communications to the West and inside Scandinavia. The invasion of Scandinavia might come at the same time or later, after a Russian invasion of Central Europe. The latter situation after a Russian victory in Europa was realised to be the far most difficult!7

Then the committee drew conclusions about the implications for the three states. The states should prepare against domes­ tic and external coup attempts. In meeting a massive Soviet invasion, it was clear that the Union would need outside support af­ ter its own initial defence against the invad­ ing forces. Therefore, the defence should be conducted as a mobile way back to “bridge­ heads” that made Western assistance possible. It would most likely be necessary to give­up large part of the states’ territory and focus the use of the forces to achieve this.

In the DNS­-scenario, Denmark and Swe­ den should prepare the defence and control of the Sound as a common project for all parts of the defence forces, e g, with the inte­ gration of Swedish coastal artillery in the effort. Mine barriers should be laid as one continuous pattern. The Danish army in Zealand should maintain Nord­East Zealand as a bridgehead for possible Swedish rein­ forcements as well as for the evacuation of Copenhagen. Danish naval forces should participate in the invasion defence of Scania, if possible, as Swedish forces should assist in the defence of Bornholm. Air and naval forc­ es might use the bases of the other countries.

The air defence of Copenhagen, where Danish­Swedish cooperation on warning and engagement of threats was essential, was not covered by the text. Ground air defence was still primarily an army responsibility, and the report only noted in the Danish defence sta­ tus that a ”decisive weakness is, by the way, the total lack of air defence of Copenhagen”. The report did not discuss how to solve that problem8, that we see repeated in our pres­ ent situation. The likely reason then was probably that the leading Danish committee member, Vice­ Admiral Aage Helgesen Vedel, focused on naval problems and cooperation, and the air forces specialists were only in­ terested in offensive and air superiority use of combat aircraft.

The outlined Danish regular land forces should consist of a sum of 18 to 19 combined arms reinforced infantry regiments of three battalions each with six to eight grouped on the Zealand Group of Islands, two on Funen, half a group on Bornholm and eight to ten in Jutland. This equalled a total of five infantry divisions.9 It was noted as important that the missing air defence of Copenhagen, an army task, should become robust. There was no text on possible Danish Army reinforcement to Sweden or Norway. The main mission of the Danish Navy should be invasion defence of the islands and defending control of the southern part of the Sound and Great Belt.

Forward basing in the South­Swedish ar­ chipelago of the larger Danish Navy vessels (“coastal destroyers”) should be investigat­ ed. The coastal fort system in the southern Sound should be expanded and reinforced with air defence weapons. The sea route across the Kattegat between Frederikshavn and Göteborg should be ensured with har­ bour defences and escort vessels. The text about the Air Force only gave the target of 15 to 20 squadrons, mainly of day fighters. There was no text about the foreseen roles of the Air Force.10

The historian Peter Bogason underlines in his monograph on the Danish Navy during the Cold War as I did in the article on the Danish armed forces 1945–1969 develop­ ment that the committee wishes mirrored the current ideas of the two services and the coming independent air force leaders, but it added extra units where this was log­ ical within the defence union framework.11

The echo of the committee work until the end of the Cold War

The work with the creation of a Nordic Defence Union did not include a discussion of the steps that would make the coopera­ tion effective such as the creation of common combined command structures. One HQ would have been needed for the land and air defence of North Scandinavia against Soviet operation from Murmansk. The fact that the Soviet activity to create supporting, specialist military maps only covered North Scandinavia underlines the relevance of close co­operation here.

Another combined HQ would be required for naval operations in the Western Baltic Sea, the Sound and Danish Belts. A third should have been responsible for air opera­ tions from and over Denmark and Southern Sweden. A fourth would be needed to plan and lead naval sea control and escort oper­ ations in the Kattegat and Skagerrak.

There had also been too little time to have concrete discussions of reinforcement of threatened areas from the other two states or reach decisions on common logistics to ease operations and mutual support, even if lists proved that work had started.

The most important result was actually the Swedish Defence Staff, Major­ General Nils Swedlund’s, PM on important areas of co­operation after the end of the talks. Even after the failure of the defence union talks, the Nordic countries should develop and agree on combined plans for radio­ and wire com­ munications, for air surveillance, for a com­ bined control of fighter defence operations, for air­sea rescue, for weather prediction, for naval cooperation in the Baltic Sea, the Sound and Kattegat­-Skagerrak with a special focus on mining, for common terminology and formats and for continued intelligence cooperation (just listing the areas listed by the general relevant for Denmark).12

In his doctoral dissertation Robert Dalsjö covered the development and fading­away of the Swedish Cold War cooperation with Western Great Powers and NATO, includ­ ing Norway and Denmark. He follows the fate of the Swedlund note, where his recom­ mendations were formally approved by the Swedish Cabinet later in 1949.13

Where Magnus Petersson’s work has giv­ en us a full description of the well­developed Swedish­Norwegian practical defence co­op­ eration14, no such research has been done in relation to the Swedish­-Danish co­operation. I know from my service as director of the Danish Joint Staff Course that the Nordic Chiefs of Defence Staffs, the officers respon­ sible for the secret defence plan coordination, visited the other Nordic capitals annually, but what was discussed or coordinated is unclear. However, I know from conversations with the retired Admiral Sven Thiede15 just before his death late autumn 2005 that he had been involved in regular meetings with Swedish counter­parts conducting the secret coordi­ nation of naval defence and mining plans for the Sound.

Preparing for this article, I interviewed the retired air defence officer, Lieutenant­Colonel Hans Adolf Schrøder, about the practical co­ ordination of the Zealand and South Swedish air defence cooperation. It was essential as the main Copenhagen air defence weapon from 1959 to 1983, the Nike Hercules sur­ face­to­air missile, had a range of 140 kilo­ metres when engaging high altitude targets. It thus covered the air space over all of Scania. In 1965 the 45–50 kilometres’ range Hawk missiles joined the Nikes. Schrøder narrated that there had been direct telephone link be­ tween the Swedish regional air defence HQs and the Danish sector HQs in Karup. The link was named “Jönsson” and was officially meant for emergency and rescue use. When the Copenhagen air defence command at the Ejby bunker outside the capital received the order “Bavnehøj”, it was authorised to en­ gage targets in Swedish air space.16

Beside the practical two areas of practical defence co­operation, the bilateral intelli­ gence cooperation with Sweden assisted in achieving warning of war and attack and updating Order­Of­Battle data on the WTO­ forces. The likely effect on Danish defence of a hypothetical Swedish activation of what Dalsjö named the “Reserve Option” follow­ ing an extended East­West crisis and early hostilities would have been very effective in a non­nuclear phase of a conflict from the moment USAF units deployed to Swedish bases. Such deployment to Swedish air bas­ es would have further to improved the air and general defence situation of Denmark.

NATO’s navies and especially the pow­ erful German Bundesmarine’s access to the Blekinge archipelago and the Karlskrona naval base and the German naval aviation’s possible use of Swedish airfields for forward deployment would have complicated or even blocked Warsaw Treaty Organisation troop landing operations in the Western Baltic Sea area. It would have been necessary for the Soviet General Staff to involve South Sweden in the landing operation and thus mirror a situation where Sweden had been a Cold War NATO member.

The relevance of Scandinavia to the Soviet Union probably increased significantly at the end for the Cold War, which is most likely still relevant. As found by the Danish histo­ rian­geographer, Stig Roar Svenningsen, in 1985–87 the Soviet Union extended original 1974–75 coverage of Europe with 1:500.000 military engineer mapping to cover the ap­ parently planned North­Western Theatre of Military Operations (TVD). The maps cov­ ered all of Finland, Central and northern Sweden’s eastern coastal areas, plus North Scandinavia in Sweden and in Norway down to Lofoten.17

The post 2004 situation in the southern and central part of the Baltic Sea

The defence situation of the Baltic States is defined by their very long border to Russia­ Belarus­Russia (Kaliningrad Oblast) and their limited capability to maintain and mobilise land forces. The combination of extremely low troop density plus high accessibility/with few obstacles to invading Russian forces is similar to the low troop density defence sit­ uation in northern and eastern Ukraine in late February 2022. The area between the main access routes can only be observed by the defenders assisted by drones, not cov­ ered with defensive positions.

Even with the resulting deployment of the four Enhanced Forward Presence battle­ groups to the Baltic States and North Poland, the NATO presence in the front­line mem­ ber states in Eastern Europe could and can only be purely symbolic, delivering a weak trip­wire presence covering so little of the terrain that it might easily be fixed by air power and bypassed, if Russia possessed agile manoeuvre forces.

To create a cohesive defensive posture in the Baltics after 2014, the combined local and allied forces would have to be developed by early reinforcement to several army corps with multiple brigades each.

As the Suwalki Gap land corridor between Poland and Lithuania is narrow and vulner­ able to attacks and fires from both Belarus and Kaliningrad Oblast, reinforcements and logistic support to the Baltic States depend on safe sea routes.

These routes of the southern and central Baltic Sea between the Swedish and German­ Polish coasts pass both the islands of Bornholm and Gotland and are still threat­ened by the long­range weapons in Kalinin­ grad Oblast.

Further north the availability of the route into the Gulf of Finland will depend on con­ trol of the Åland and Estonian Islands. Safe use of the sea routes depends on NATO sea control of the Baltic Sea and effective air su­ periority to protect the shipping.

Post 2022

Besides the threats of invasion and attacks on sea routes, all countries of the area lie exposed to bombardment with Russian pre­ cision cruise and ballistic missiles as the Ukrainian cities are now. The threat from Russia is hereafter increasingly one of ar­ tillery supported limited coups and terror bombardment rather than general invasion.

The situation in the Baltic States and the Baltic Sea influence how a Swedish and Finnish NATO membership will influence Danish defence. It will, however, depend on how the two states define their membership in relation to force contributions, national and military readiness and allied peace­time basing rights. The assumption here in rela­ tion to the last issue is that the membership will be without nuclear weapons and per­ manent bases in peacetime.

As already noted, the Danish politicians have not yet faced and concluded what the Russian invasion of Ukraine and the increased and more explicit threat to the Baltic States and the rest of Eastern Europe means for the future of the Danish defence missions and organisation.

However, the following is already clear from their actions and statements:

1. Firstly, that the increased U S focus on the Arctic and specifically Greenland has led to a political decision to increase the Danish military presence there.
2. Secondly, that even if the implications are still unclear, the Baltic Sea and the Baltic States will once again be a Danish Defence Forces’ priority area.
3. Thirdly, it has become a basic premise that Denmark is no longer the directly inva­ sion­threatened front­line state area it was until 1989. The main part of the country is now a NATO rear and potential transit and base area. This third factor is reinforced by Swedish­ Finnish NATO membership. The implications of Bornholm’s special geostrategic position on the sea routes to the Baltic States and halfway to the Russian bases in the Kaliningrad Oblast are probably not yet clear to the politicians, but I shall cover it later.
4. Fourthly, even before the Swedish­Finnish applications there has been political decla­ rations of political will to increase and deep­ en the Nordic States’ defence co­operation. Now the co­operation without limits from different alliance status that was discussed in 1948 is possible, Whether the co­opera­ tion will be enhanced by the new situation is not at all certain, even if increased stand­ ardisation of materiel and training cooper­ ation would seem to be logical.

The Arctic and North Scandinavia

The Swedish­-Finnish NATO membership is relevant in the north for two reasons: Because the defence of the main Norwegian position in the Troms area has always been threatened by a Soviet/Russian advance from north­western Finland through the Skibotn Valley, continuing over the mountains by­ passing the “Lyngen Line” either directly or outflanking it further south via Swedish ter­ritory. The object of a Russian invasion of North Scandinavia is an updated version of the described 1948 analysis: it would create a defensive and potential offensive buffer in front of the Northern Fleet bases in the Kola Peninsula and ease the access to Atlantic and its sea lines, making it possible to de­ fend the Polar Sea SSBN deployment area and the western end of the less ice hampered North­-East Passage along the Russian coast.

With Sweden and Finland in NATO it would be both logical and essential to form a common combined and joint subregion­ al allied HQs for the defence of Norway plus North Scandinavia against any Russian Northern Fleet offensive, even if it must be considered beyond the present capabilities of the Russian armed forces.

Whether this becomes directly relevant for Denmark depends on the link to the potential U S use of bases in Eastern Greenland and Iceland to gain a more effective control of the sea between Scandinavia and Greenland. The framework for this might be a region­ al arctic HQs where a subregional HQs in North Scandinavia would be the eastern anchor made robust by all Scandinavia be­ ing in NATO.

It is relevant to note that this U S interest in the Arctic and North Scandinavia will continue even after an end to involvement in other parts of NATO as it is linked to the continental defence of North America and the position of the U.S. as a major naval power.

Denmark and the Southern half of the Baltic Sea

The Swedish NATO membership is poten­ tially important in three areas. In relation to Denmark’s potential situation as a rear base and transit area for the alliance defence of the Baltic States, Finland and Poland (as Copenhagen had last been from 1918 to 1920). It is also relevant to the potential role of Bornholm on the Baltic Sea lines of oper­ ations. Finally. it is important for Denmark’s potential for participating in the forward defence of the Baltic States as part of the

Alliance contribution
The logical way of organising the solu­tion of NATO­-missions in the Baltic Sea and littoral areas would be to create a regional command for the entire area including the entire Baltic Sea from the Kattegat and the Danish Straits to the Gulf of Bothnia and the littoral from Denmark­-Schleswig­-Holstein via the German and Polish coastal areas to the Baltic States and Finland and Sweden with the exemption of Finnish and part of Swedish Lapland. It would be an adjusted successor to the AFNORTH of the Cold War era, moved southeast with its HQs in Sweden. One of its subregional commands un­

der such a regional HQs would cover the front­line member states of Finland and the Baltic States, another with the rest, mean­ ing the transit and base areas in Denmark­ Schleswig­Holstein and Sweden with the naval component commander also respon­ sible for the islands that must be defended against a Russian pre­emptive coup, meaning primarily Bornholm and Gotland. Until the reconstruction of the Russian ground forces, such coups are probably the maximum of­ fensive steps that may be attempted. As one precaution it would finally be logical for the main units of the Danish Navy to operate from Karlskrona as had been suggested in the Scandinavian Defence Committee in 1949.

The Russian possibilities in the Baltic Sea will be limited to mining and missile attacks on NATO sea lines. Two factors will de­ cide how much or little harm the Russian forces can do. Firstly, whether NATO risks using robust force to suppress the Russian missile batteries in Kaliningrad. Secondly, the strength of NATO air forces deployed to Sweden in crisis and war. Presently and in the near future only the USAF have such forces available.

As already noted, Russia is likely to use conventional cruise and ballistic missiles against enemy cities in any war. The secret Cold War Danish­-Swedish air defence co­ operation should inspire the creation of a common air defence command for the Zealand­Scania area covering Copenhagen­ Malmö to meet this missile threat. It should integrate all existent and future, medium and long­range air defence warning and air defence missile assets that could contribute, both ship based and systems on land.

Until a very significant rearmament in Europa has been achieved, the security benefits of Sweden and Finland’s NATO mem­bership to Denmark and the existing mem­ bers of the region depends on the continued involvement of the U S in the defence of the European NATO members.

Conclusions

Everything in NATO and the relations be­ tween its European member states depends on continued U.S. armed forces engagement in their defence against Russia. Even if Russia has demonstrated weaknesses in their armed forces that will be very hard to address with­ out extensive political and economic changes, the last months have highlighted how im­ portant the American contribution remain.

It is not meaningful to have any discussion of the structure that is to mirror and define the mutual roles and cooperation without clarifying the assumptions on that contribu­tion. Without a U.S. intent to support the de­fence of the Baltic States with strong airpow­er deployed to Northern Europe, the game is still open in spite of Russian limitations.

The Western planning for if and how to deal with the Russian bases and forces in Kola and Kaliningrad that define the op­erational problems in the Arctic and Baltic areas is to be decided by the U.S. Swedish and Danish choices that will de­ fine the mutual relationship and interde­ pendence between their defence situation and cooperation is to be limited by deci­ sions of others.

The author is brigadier general in the Danish army and former commandant of Baltic Defence College.

Foto: NATO