Gotland's importance for NATO's ability to support the Baltics in the event of a Russian attack has long occupied a central place in the Swedish defense debate. And rightly so. However, there are more islands in the Baltic Sea that could have a major operational significance in a conflict affecting the Baltic Sea area. Islands that, if they fell into Russian hands, would also pose serious problems for NATO in the defense of the Nordic-Baltic region. Often bigger problems than might appear at first glance, but where the islands can also contribute to increasing NATO's warfare capability if they are utilized in the right way.
Below are some thoughts on the importance of Åland, Gotland, Saaremaa/Dagös and Bornholm in relation to military operations in the Baltic Sea area. The perspective can be perceived as somewhat Sweden-centric, but this is intentional. As a non-immediate “frontline state”, with a land border with Russia, Sweden is the country in the region that should be able to allocate the most resources to handle various developments in relation to the islands in the Baltic Sea. Furthermore, due to the short geographical distances, they can be deployed fairly quickly.
Åland Islands The significance is threefold. Two problems are linked to how Russian long-range weapon systems on Åland could affect NATO's naval and air operations and one to the protection of maritime transport in the Bothnian Sea. It is obvious that transport to and from southern Finland and the northern Baltics by air or sea would become more risky with Russian long-range weapon systems grouped on Åland. In addition, the presence of such Russian systems on the archipelago would also make allied air operations over southwestern Finland and parts of eastern Sweden more difficult. It is approximately 120 kilometers from Mariehamn to Uppsala and about the same distance to Turku. Not unusual ranges for modern air defense missile systems. In addition to the fact that NATO's naval and air operations could be affected, another serious problem arises if Russia were to succeed in occupying all or parts of the archipelago. The Swedish and Finnish possibilities of preventing Russian submarines from passing into the Bothnian Sea by laying mines and taking other measures in the Åland archipelago would be jeopardized. This would threaten maritime traffic between Sweden and Finland across the Northern Kvarken. But also transporting goods by sea from Central Sweden to Norrland would become considerably more dangerous. Transports that are important from both a military and civilian perspective. Civilian from a supply perspective, military in terms of being able to bring troops and supplies to Finland and northern Sweden. The possibilities of being able to carry out transports to Norrland via the Bothnian Sea could be crucial for the defense of the North Calotte, given the vulnerable land connections through Sweden. Between Mälardalen and Luleå there are ten major rivers, with a few connections across each. Bridges have long been a welcome target for various precision-guided weapons.
The Åland Convention from 1921 complicates Finland's, and thus NATO's, defense of the archipelago as it prohibits military presence on the archipelago in peacetime. However, it does allow the archipelago to be defended. The Swedish-speaking Uusimaa Brigade, with headquarters in Dragsvik on the Finnish mainland, has long had the task of quickly occupying and defending Åland in the event of a threat of war. Considering the size of the archipelago, 6700 larger and smaller islands, its geographical location and its importance for both Sweden and Finland, it should be obvious that Sweden also earmarks a number of units whose primary task is to defend the archipelago together with the Uusimaa Brigade. We are talking here about one or more amphibious battalions.
Ösel/Dagö (Saaremaa/Hiiumaa) is rarely mentioned in the debate (at least not in Sweden), but a loss of the islands, with the consequence that Russia would have the opportunity to group naval and air defense systems there, would have serious consequences for NATO's ability to reinforce Estonia directly by air or sea. But traffic in Finnish ports in the Gulf of Finland would also be jeopardized. It is often emphasized that Finland and Estonia together could block the Gulf of Finland for all naval activities that take place above the water surface. That is true. But a Russian possession of Dagö would mean that NATO's naval traffic in and out of the Gulf of Finland would also be seriously threatened. The distance from Dagö to Hanko in Finland is less than 100 kilometers, a fairly short distance for modern anti-ship missiles. From Sasel it would be possible to interrupt all naval traffic in and out of the Gulf of Riga and also threaten traffic in Ventspils, Latvia's most important port on the Baltic coast. The distance from Saaremaa to Ventspils is approximately 60 kilometers.
It is no coincidence that Estonia, despite the strong threat at the land border with Russia, which requires most of the country's military resources, is still acquiring anti-ship missiles. In addition to helping to block the Gulf of Finland, it must also be able to meet coup attempts against Saaremaa and Daugava. Neglecting the defense of the islands would be a big mistake, but it is not an insignificant task. Especially not for a country with a total of 1,3 million inhabitants. Saaremaa is almost as large as Gotland, approximately 2600 km2 and approximately 3000 km2 respectively. Daugava is almost twice the size of Bornholm, approximately 1000 km2 and 590 km2 respectively. Here, as in the case of Åland, there are good reasons to consider whether Sweden could not play a role in strengthening the defense of Saaremaa and Daugava even during a crisis, and also be able to contribute to retaking the islands in the event that they were fully or partially occupied by Russia in the initial stages of a conflict. Here, as in the case of Åland, Swedish amphibious units would probably be a suitable instrument with their organizationally integrated sea transport resources. Depending on the overall situation, Finnish measures to contribute to the protection of Saaremaa and Daugava should not be ruled out here either.
As an alternative, it would be interesting to study in more detail whether the islands can be defended from the Estonian mainland only by using various indirect systems such as artillery and drones. A method that has often been advocated in various contexts over the past hundred years but has rarely succeeded in practice. However, what we are seeing in Ukraine today represents a technological leap that could perhaps make such a concept feasible. The distances at which the systems would need to operate are less than 100 kilometers, which would allow for operations with quite a few different weapon systems.
Gotland The importance and the danger that Russia, with long-range anti-ship and anti-aircraft systems from there, could hinder NATO's ability to bring reinforcements to the Baltics has been given much space in the debate. There is considerable consensus that the island must therefore have an adequate defense. However, two aspects should be highlighted here. One that seems to disappear in the general joy that units from allied countries are exercising on the island, and are assumed to contribute to the defense of Gotland. This can certainly be the case in situations where we have received sufficient advance warning that a conflict may be imminent, and that our allies have units that can be seized at short notice. The problem with such an approach, especially in the case of Gotland (and other islands in the Baltic Sea), is that the warning period for an attack can be very short.
Russia's ability to conduct amphibious or airborne operations in the Baltic Sea area after the outbreak of war will be limited. The ports from which the operations could be launched, Kronstadt and Baltishk (in the Kaliningrad exclave), will in practice not be usable due to NATO countermeasures. The Gulf of Finland will most likely be blocked by Finland and Estonia. Baltishk is less than 40 kilometers from Polish territory, and the outlet of Frisches Haff (the lagoon where the naval base is located) will probably be mined by NATO at a very early stage of a conflict. Likewise, it will hardly be possible for Russia to conduct any major airlift movements across the Baltic Sea in that situation. The best, perhaps only, opportunity for Russia to take Gotland is if that operation is the one that starts the war, and if it can be carried out with reasonable surprise.
This means that our, NATO's, planning for the defense of the island should be based on the fact that a coup d'état occupation of the island can be averted with existing resources, and not assume that reinforcements, Swedish or foreign, will be provided in time. The current direction for the Swedish military presence on Gotland (according to the defense committee's proposal and ÖB budget documents) is insufficient. One battalion reinforced with artillery and air defense is not enough. Rather, we should be talking about double that. And just as important, all units on the island should mainly be manned by personnel living on the island. That would be entirely possible, if one wanted to. The population base on Gotland is sufficient to deploy up to approximately 5000 people (approximately the number who mobilized on the island during the Cold War). Something that should be enough to double the currently planned organization. Of course, that would mean that the number of Gotlanders who did military service, proportionally speaking, would be considerably more than what applied on the mainland. But it should not be impossible to create incentives that made such an arrangement possible. Not everything needs to be exactly the same across the country. As a curiosity: on Gotland, a type of general conscription was introduced as early as 1812, Gotland's national conscription, that is, almost 90 years before the same thing happened on the mainland in 1901. Also at that time, it was based on the realization that the defense of Gotland placed special demands on preparedness. This as an experience from the surprising Russian occupation of the island in the spring of 1808.
The second aspect is that we too rarely discuss the opportunities that Gotland gives us, NATO, to limit Russian freedom of action in and over the Baltic Sea. Or put another way: how can we use the island to increase the alliance's ability to defend the Nordic-Baltic region. Here are some opportunities to use the island to increase the alliance's warfare capability: grouping sensors to receive early warning of aircraft and cruise missiles approaching the mainland; the island can constitute a "first line of defense" to meet threats to the mainland with qualified air defense systems; signals reconnaissance; basing submarine chaser helicopters on the island to give them increased endurance; protecting and supporting our own air resources operating over the Baltic Sea with our own long-range air defense; forward base for drones for both maritime surveillance and operations in the Baltics; grouping ground-based missiles for operations in the Baltics, which is just over 500 kilometers to the Latvian-Russian border. Some of the tasks above were already relevant during the Cold War, for example using the island as a sensor platform. Weapons developments since then mean that the island could be given a significantly more active role today than was possible then.
Bornholm's location in the southern Baltic Sea would make the island an optimal platform for primarily various long-range anti-ship systems with the aim of preventing ships passing through the Belts and the Sound from entering the Baltic Sea. The distance to the Swedish mainland is about 40 kilometers and to the Polish coast it is about 100 km. Today, fairly short distances for anti-ship missiles. Nor should the distances be any major problem for sensors based on the island for target acquisition, e.g. drones. From a Russian point of view, if Bornholm is successfully occupied, perhaps the big problem is that the island is so small. The possibilities for hiding bulky missile launchers with support systems are quite limited. However, the total ruthlessness that characterizes Russian warfare will likely mean that civilian infrastructure such as schools, hospitals, etc. will be used as “shields” for military operations and grouping of various weapon systems. Something that could probably lead to some hesitation on the part of NATO to fight even identified targets. A problem that will be relevant not only on Bornholm. When it comes to the defense of Bornholm, the problems are similar to those discussed above regarding Gotland. The island's own military potential, including in terms of manning the units that will defend the island, should, for example, be utilized as far as possible. It must not be an attractive opportunity for Russia to try to occupy the island in a coup just before, or in connection with, an outbreak of war in the Baltic Sea area.
In summary. Åland is a joint Finnish-Swedish problem where Sweden should be able to make a substantial contribution to the defense of the archipelago. The importance of Ösel/Dagö is rarely noted in Sweden, but is also an area where Swedish efforts could make a difference. In both cases, primarily with amphibious units, which suggests that this component of the Armed Forces should be expanded quite radically. The need to defend Gotland is not questioned in Sweden, however, there is reason to review how the defense is organized and how the island is used to strengthen NATO's warfare capabilities in the Baltic Sea area. Bornholm's central location in the southern Baltic Sea means that the island should be given a defense model that is primarily focused on warding off a coup d'état attack. In summary: the islands in the Baltic Sea are not only places that must be defended to prevent Russia from exploiting them, they are also an asset for protecting other parts of the Baltic Sea region, and they can and should also be used as platforms for various types of operations in support of the alliance's defence of the Baltics.