For reference:
The energy or "power" of a 0.45 cal auto round of ammo is about half that of a NATO 5.56 mm round, which is about half that of a NATO 7.62mm round. The NATO 7.62mm is more powerful than the 0.303 cal of WWII. Added bonus for you 9mm fans: 9mm packs about half the power of a 0.45, it just uses a much smaller round to increase the velocity. Having extensive experience using both, I prefer and carry a 0.45 on daily basis, but also have a Beretta for show and tell (they are almost as pretty as a 0.45).
But, if you think a 0.45 won't hurt anything, buy one, walk out to your car and proceed to fire. The engine block will be unhurt, but it will punch a very large hole in just about anything else it hits. One round in the right place will shoot any plane down, however low the probability of finding that right place

I would only question the effective range. You can't hit still targets the size of a man much farther than 25 yards away with a government issue weapon (I have 8 years of struggling to fire goverment issue 0.45's in the Navy to back that up). My personal 0.45 is a completely different story

[This message has been edited by streakeagle (edited 04-16-2001).]