This is the highest law in America, and any country should be careful before changing its laws, so these arguments need to be addressed. The second amendment to the US Constitution, where the right to bear arms is guaranteed, was written to enable the citizens of the new country to defend themselves against possible attack from England if it sought to retake its recently free colony.
Obviously this particular situation n is no longer a worry, and so the very basis for the right to bear arms no longer exists. Another argument for gun control is that once the sales of all guns (except those used by farmers etc.) is banned the number of crimes that use guns will eventually go down. At first, because there are so many guns in existence, this may not occur, but guns are complex tools that need maintenance and replacement on a regular basis. Eventually most of the handguns in existence would become unusable, criminals would not be able to get hold of them and crimes would be committed without the use of a gun.
A major reason for gun control is the number of young people and even children who accidentally kill themselves while 'playing' with guns they have gound that belong to their parents but which have not been securely stored. More than a thousand children a year die in this manner. Hundreds of others are killed in violence between children/teenagers that turns deadly because they have access to guns.