Is the number of guns the major problem?
37% of American households said that somebody in their home has a gun. Taking into account that there are 123 million households, we can estimate that 45 million Americans are gun owners, i.e. 14% of population owns guns.
In Israel any active duty soldier (175,000) twice a month rest at home and keep his/her gun. Moreover 445,000 reserve soldiers have guns and allow carrying them outside of military compounds. There are 600,000 registered guns in citizen possession. Assuming that half of soldiers have also registered non-military guns we can estimate that 11% of population has regular access to guns
Homicide with firearms per 100000 citizens:
Israel 1.04 and USA is 3.55