We like to think of NATO (North Atlantic Treaty Organization) as the defender of Europe during the Cold War era against the threat from Russis. However, NATO has become much more than that and is now involved in many regions of the World. They then drag the USA into these affairs as well.
They are connected to the UInited Nations and are the policemen for the UN to some extent.
Whether we (the US) drag NATO or NATO drags the US into conflicts is up in the air. But there has always been a flow of senior level people between the US and NATO and vice versa.
A more thorough analysis needs to be done of the role of NATO and our connection to it. Watch this link from www.jbs.org for their conservative view.
NATO's role in supporting the various controversial "trade partnerships" also nees to be checked.