Blimey
I should have remembered how Americans feel about their fave handgun ammo! Criticizing .45 ACP seems to be the equivalent of doing a cartoon about the Prophet Mohammed in some quarters.
Please note, gents, I didn't say .45 is rubbish, I just said that cops, soldiers and crims are mostly - note that, mostly - using other calibres these days. That's just a fact, not an aspersion or an opinion.
On the matter of .45's virtues or lack of them, one of the main criticisms against it is poor armour penetration, which I tried to cover in the bootnote - evidently inadequately. Fairly low muzzle energy and a big bullet naturally mean bad penetration, as the number of joules per square mm is comparatively low. That's all. Even higher-energy, smaller diameter pistol slugs like hot 9mm, .357 mag etc have troubles against modern armour - that's why people have brought out things like Russian 9x21mm or the new Euro steel-needle type rounds, 4.6x30mm HK and 5.7x28mm FN.
Of course, as some home-defence enthusiasts have noted, the average crackhead burglar won't be wearing a vest - if he had a vest he'd have swapped it for crack - so .45 is a valid choice against him. Personally, though, it seems to me that inside one's own home there would seem little reason to restrict oneself to pistols if one is having a gun at all. As the old gag has it, handguns are carried by people who don't expect to fight - if they did, they'd arm themselves properly. Don't bring a knife to a gunfight, sure - but frankly if you have a choice don't bring a pistol either. If I were an American, buying a gun for fighting inside my house, I'd probably go for a shotgun if I could get one that held a decent number of rounds and short enough to use in confined spaces. (I think there's a US law about minimum barrel length?)
Those much more advanced in CQB than me tell me that a submachinegun or a carbine is better, but they *are* worried about body armour and -crucially - they are very good shots and much better at maintaining situational awareness than I am. Like most people here I suspect, I've never been in a gun fight and while I'm a reasonable shot on the range (or was, haven't fired a weapon since I left the service in 2004) I expect my performance would drop off pretty sharply with the brown adrenaline flowing. With a shotgun I'd be confident of seriously messing up anyone I could manage to hit, and also of not sending bullets through them (or through walls, ceilings, floors etc) to hit my family and neighbours.
Of course I'm not an American so I' m effectively not allowed to keep a gun in my house. That doesn't bother me that much - I'd probably have one if I lived in the States, just for fun, but the lack of one doesn't bother me. I'll back myself against a crackhead burglar with whatever I can pick up around the house (if the burglars down my way had guns, they would swap them for crack, so I don't worry about armed intruders. Guns and vests both are apparently quite common among the criminal fraternity in my neighbourhood, but only among management and sales, not the drug users).
As for defending myself against the guvmint, well. As someone here has already pointed out, the government's got you outgunned. When the feds come to take your guns away, gentlemen, .45ACP is going to be a poor choice indeed - the SWAT team *will* have armour on, and even if you're Wyatt Earp himself you'll struggle to get them all in the head. And if you choose something a bit more modern and manage to piss them off, they'll still win - ultimately they'll blow up your house with you in it, as they already tend to do when pressed for time overseas.
If you actually want to get into that sort of fight, reach for your roadside bomb rather than any kind of gun. And give up on "home defence", too - permanent homes aren't safe for freedom fighters/terrorists.
But come on, FFS, everyone. The US government isn't that bad. Gun-loving Yanks aren't that bad. Gun-hating limey weenies aren't that bad. Let's all just be friends and look forward to pub time (unless we're down on alcohol of course, FFS don't all get cross again).
PS - gun guys - for the record I have shot .22 pistol at uni back when it was legal. I had to stay qual'd on the SA80 5.56mm rifle and 9mm Browning pistol for most of my 11-year service career, and latterly as 2ic or boss I tended to shoot more than strictly required because I liked it and nobody could stop me. I have also fired other weapons now and again, including a .303 Lee Enfield as a boy, Sig Sauer and HK MP5 9mm on the SBS ranges at Poole, 7.62mm GPMG on the Commando course, shotguns once or twice, airguns when a lad etc. I even fired an acquaintance's .45 once when I was working in the States during student vacations.
I'm sure I don't shoot as much as many of you, but I'm not totally ignorant.