I don't really have any opinion about US gun law, its up to the Americans to decide. I think perhaps the sad thing is there's a clash of culture, that for a good portion of Americans gun ownership is part of their culture, while for the rest it isn't, and its in the nature of the topic that it isn't really possible to satisfy both groups. (I do wonder if the South had won the civil war, whether the North would have developed more of a European political culture, with European style gun laws, while the South became like Apartheid South Africa before eventually ending up a black-majority nation, like post-apartheid south africa...but, um, thats a bit of a tangent).
Anyway, guns don't kill people, criminal and crazed people kill people, unfortunately US society seems to produce an awful lot of those. I'd think that was an argument for changing the society more than banning the guns.
I also think its supremely ironic that, apparently, some of the hostility to the US in Iraq has been partly fuelled by the US forces attempts to disarm the population, gun ownership being very widespread under Saddam (not that that seemed to do much to 'prevent tyranny'). Did the NRA have anything to say about US troops raiding people's houses in Iraq to sieze household guns?
But even in the UK, with, I think, the tightest gun control laws in the world, shootings seem to become more and more frequent. They are certainly commonplace in South London now, where once they were almost unheard of. It seems there's some sort of inevitable increase in the destructive power available to individuals, whatever the law says.