Guns do not equal violence. It's the people who use them in this way who are violent. You'll note that there are numerous countries with similar gun laws to the US without such high homicide rates. Don't get me wrong; I do think the mentality of 'it's my god-given right that I can own/carry a gun' is a silly one, but availability isn't the problem.
The notion that if the government were to tighten gun control the situation will only worsen is correct. What exactly would motivate criminals willing to commit murder to give up their arms?