Those 60,000 would have gotten hurt or killed anyways by the ones wanting to do so. The gun was the tool, not the cause.
Not neceserily. For example the situation about the Florida guy. If guns were illegal, there would be a better chance that he wouldn't have a gun, in which case, the victin would've had a better chance of surviving (say, if he brought a knife, he could've ran away etc.).
Yes, gun is a tool, just like a knife, baseball bat and so on, but it is a tool that is harder to escape death from.