Well, I've read all ten pages of this thread, and now my head hurts. If I may, allow me to sum up what I perceive to be the two extreme sides of this argument, and then my rebuttals.
"Guns are evil! Ban all guns, take all guns away from law-abiding citizens, and then no one will ever have guns!"
I'm sorry, but no. Unless there were a law-enforcement crackdown on illegal weapons the scope of which has never been seen before in America, there is absolutely no chance that even a slim percentage of the illegal weapons currently in possession of criminals would be siezed. Thus, you would have a disarmed populace and a still-armed criminal element. We do not have police on every street corner ready and waiting to pounce on criminals the instant they have a nefarious thought; some cities have reported 15 to 30 minutes between a call to 911 and a police cruiser arriving on-scene. While the following quote may be pro-gun propaganda, it also rings true far too often: "The police arrive just in time to draw a chalk outline around a body".
"Leave my guns alone! The gub'ment's gonna try to take my home and I'm gonna shoot 'em! Guns keep me safe from a repressive government!"
I'm sorry, but no. I honestly believe that the vast majority of people who claim this would, upon being confronted by a heavily-armed SWAT team, put their hands up and surrender quietly. It's all well and good to claim that you are the first, last and only line of defense against a government who is just waiting on that last order of black helicopters before they come to take you away, but when it comes to your 15-round magazine of 9mm ammunition versus a police sharpshooter and a ten-man team of trained officers with ballistic shields and shotguns, your chances are nil and you know it. It may be that the government will overstep all bounds someday, but don't even try to glorify it or make yourself out to be the next justice-bringing gunslinger.
Now. A little about me. I am a social liberal and a fiscal conservative; I believe that the government can do more with less. I do not belong to any political party, lobbyist group or "club" such as the NRA or MoveOn.org. I am also a casual shooter who qualified for a concealed-carry license at my first visit to a range, someone who received a general discharge from Army basic training after qualifying as an expert with an M16A2, and someone who hopes to one day become a professional competitive shooter despite the fact that I do not currently own a firearm. I can also refer to two occurances which show the value of an armed populace, and the danger of disarming one.
1) The North Hollywood Shootout [http://en.wikipedia.org/wiki/North_Hollywood_shootout].
In a nutshell: Two previously-arrested felons, heavily armed with illegally-modified weapons and illegally-obtained ammunition, protected by considerable body armor and heavily dosed with barbituates, instigated a bank robbery and then engaged in a 40-minute shootout with police. The standard-issue 9mm and .38 rounds the officers were issued were useless against the body armor, and they actually had to requisition semi-automatic rifles from a nearby gun store until SWAT teams could move in.
Two men held off an entire police force for forty minutes. Can you imagine what an entire group of people like that could do, if their intent was to kill instead of rob?
Maybe something like this.
2) The terrorist attacks in Mumbai, India [http://en.wikipedia.org/wiki/26_November_2008_Mumbai_attacks].
I don't think I need to go into much detail with the "what happened", considering how recent this event was. However, think about this: India has some of the tightest gun-control laws in the world outside of abjectly banning them outright. Yet it is reported [http://blogs.reuters.com/pakistan/2008/12/11/time-to-relax-indias-gun-control-laws-to-fight-militants/] that black-market weaponry of the grade the attackers used could be had for as little as $1500 (US) a piece. It took Indian security forces three days to regain control, after which nearly two hundred people had been killed and another three hundred were wounded.
Ten men held off an entire country's armed response for three days. Could these terrorists, none of whom wore body armor, have been stopped sooner if the citizens and tourists had been armed?
America already has stringent gun laws on its books already. The issue is that they are not enforced nearly as well as they should be. I am in favor of gun licensing and training, heavy penalties for crimes committed with firearms, and improved funding of police departments. Your average homeowner does not need ready access to weaponry designed to take on armored vehicles. But to say that all it takes is a law to disarm everyone, and that everyone will be safe, is the absolute height of fantasy. It's not going to happen in this world anytime soon.