The UK is one of the founding members of NATO and is arguably the second most important military power behind the US. This status is arguable because Germany, Turkey and Italy, not to mention France have become increasingly important while the UK military forces have shrunk considerably since the formation of the Alliance. In 1994 the British military had reduced to about 250,000 personnel, relatively small compared to other nations and a shadow of its former strength, but this force was technologically advanced and highly proficient.
Territorial commitments, disputes and agreements are too numerous to mention but the UK has global commitments which it struggles to maintain. For a better understanding of the entities that make up the UK, you may wish to watch this humorous but accurate video. However despite the difficulties, since the 1982 Falklands war the downward spiral of funding and neglect has stopped and British forces have been a keystone force in the Gulf War, Yugoslavia and Bosnia. There are also continuing commitments to Northern Ireland, Belize, Brunei, Hong Kong, Kenya, Cyprus and Gibraltar.