This study aims to analyse the overall military capabilities - especially with re-spect to operations in Northern Europe and the neighbourhood of Sweden - of the US armed forces in Europe today (i.e. 2016-17), and the changes in these capabilities that can be expected over the next four years. Analytically, it aims to identify the driving forces that explain the changing US military presence in Europe. Today, the United States has a strategic headquarters (US EUCOM) and a total of about 63,000 military personnel permanently based in Europe. In terms of ground forces, two light brigades are permanently based on the continent and a heavy brigade rotates permanently in to Europe. The US Army in Europe (USAREUR) has large training facilities for land-based warfare at its disposal and has begun storing materiel and supplies for additional units. In terms of air power, the US has more than 150 advanced fighter jets based in Europe, which is comparable to e.g. the Spanish Air Force. In addition, the US Air Force in Europe (USAFE) has tactical-strategic nuclear strike capabilities and substantial air refuelling resources. In terms of sea power, the US 6th Fleet headquarters is based in Naples (Italy), as is the command ship USS Mount Whitney. Four US AEGIS destroyers with missile defence capabilities are permanently based in Spain. The Marine Corps presence and basic facilities in Europe have also been strengthened in the last few years. Furthermore, the US has some special forces capability in Europe and is building up advanced missile defence systems in Poland and Romania. The planned changes to the US military presence in Europe concern primarily the ground forces. Altogether, by the end of 2017 the United States will have two permanently based light brigades, one permanently rotating heavy brigade from the continental United States, as well as prepositioned equipment in Europe for an-other two heavy brigades. Overall, this equals a reinforced division. There has been almost a tripling of heavy US manoeuvre battalions since 2012. In addition, prepositioning of Marine Corps materiel in Europe is increasing. Furthermore, other Marine Corps units and airborne troops from the continental United States can reinforce the military units in Europe. Taken together, all this represents the main elements of an army corps. Such a unit can handle most tasks in Eastern Europe within a week. Given the peacetime basing of most of the units involved, the US capabilities to carry out defence operations in the neighbourhood of Sweden have increased significantly since 2014. The main explanation for the increase in the US military presence in Europe that has been implemented since 2014 is the Russian aggression against Ukraine. A tentative conclusion is, thus, that it is geopolitical threats, rather than domestic political factors or economic problems, which govern US the military presence abroad. A conclusion that can be drawn from this is that the US security and defence policy toward Europe today mainly is governed by the kind of armed solidarity that has been the foundation of this policy since the end of the Second World War, although at lower levels of troops and armaments compared to the Cold War era.