There are millions of safe and responsible gun owners in the U.S. The number of gun related crimes relative to the number of total guns owned is less than a fraction of 1 percent. (See http://en.wikipedia.org/wiki/Gun_violence_in_the_United_States#Gun_ownership for more statistics). This means that a large portion of the gun crime is committed in a very small minority of gun owners. Attempts have been made to reduce these gun deaths by restricting the sale of guns and requiring background checks. However, criminals always find ways to gain an advantage over rivals and to gain weapons illegally. While these methods have some value, they are not the only solution.
A large portion of gun crimes and gun related crimes can be traced to drugs, alcohol, and other addiction/substance abuse problems. Gun use in gangs and criminal organizations has been commonplace for over a century (think Al Capone). Perhaps, the restrictions and enforcement should focus on dealing with the underlying issues in gun violence, rather than on the guns itself. While the U.S. has a higher than average gun crime rate, the rate for assaults and robberies are on par with similar countries. What this means is that in violent crimes in other countries, bladed or blunt weapons are used instead of guns. And yet, you don't see the call to ban knives or baseball bats.
To solve the issue of gun control, one will have more success if the focus is placed on prevention of situations in which improper gun use could result. This could mean more money spent on tackling drugs, gangs, domestic violence, and other problems where guns may be used. The Supreme Court has ruled and guns are here to stay. Now, the emphasis must be placed on preventing situations where improper gun use is the highest.