Originally Posted by
Tourist
Neither have you by the sound of it.....
The idea that "defence of the realm" is best done at home is fallacious as any student of history will tell you.
Always fight on the enemies territory, and for that you need expeditionary.
Probably didn't put it very well, was trying to be distinct between defending ourselves and (for example) trying to police the world with the US.
(Bit simplistic, it's a lot more complex than that).