"We thought we could avoid WWII that way but finallly had to face up to the fact that if we stood alone long enough we'd probably lose our freedoms."
What freedoms are you talking about? Constitutional freedoms? Those was never the slightest risk of being conquered and deprived of our Constitution by either the Germans or the Japanese. Now, the freedom to go wherever we want and do whatever we want (called "American Interests", or American hegemony), those "freedoms" were at risk, sure.
But WWII is such a bad analogy to the current conflict, I don't know why you even bring it up. The Cold War is more apt. Or even what Philip Bobbitt calls "The Long War", by which he means everything between 1914 and 1990.
We have sufficient combat power to take down a rogue regime, just not sufficient US troops to police a country of 25M. But that's OK, because we don't have any business using our conventional forces for that purpose anyway. That's what the force multipliers in Special Forces are there for.