Under the terms of NATO membership, an attack on Montenegro would be treated as an attack on the United States, Canada, Germany or any other NATO nation's home soil and we would be obliged to react appropriately.
The only country that considers Montenegro strategic is Serbia, since the port of Bar (a city, not a pub) which the Serbian government is trying to purchase, is Belgrade’s only link to sea lanes since the collapse of Yugoslavia.
In 1999 NATO conducted an air war against Serbia, so it may be said to be hostile. However, as improbable as it seems, However, the Serbian military frequently trains with the Ohio National Guard (don't ask me why because I don't know).
My question is WHY? With respect to the people of Montenegro - I don't know any of you and if I did, I'm sure I'd like you, I don't want to go to war if you decide to do something stupid. Why do we want to link ourselves by treaty to Montenegro?