Stating that more guns are the reason there are more mass shootings is like stating that more automobiles cause more automobile accidents, I'd say the better question would be
what explains intentional homicide worldwide?
Reducing the number of guns does not reduce the number of intentional homicides, for example Russian gun ownership per capita is estimated at around 8.9 per 100 people and Mexico at 15 both of which have very strict gun control policies while the United States stands at about 101 guns per 100 residents. the
intentional homicide rates of each respective countries calculated per 100,000 residents are as follows:
Russia 11.3
Mexico 16.3
United States 4.88
List of countries by intentional homicide rate - Wikipedia
Estimated number of guns per capita by country - Wikipedia
a few more comparisons:
Brazil: 8 guns per 100 people and an intentional homicide rate of 26.74 per 100,000
South Africa: 12.7 guns per 100 and an intentional homicide rate of 34.27 per 100,000
Using these figures one could argue if we reduced the number of people then we could reduce the number of intentional homicides, it's a people problem.
If you were capable of making and implementing gun control policies in the U.S to reduce the numbers of them, how would you go about it?
For example:
Would you be willing to confiscate legally owned firearms from law abiding citizens and would they be fairly compensated for their property seizure?
What would be the penalty for otherwise law abiding citizens for not turning in firearms within a specified time, fines? jail time?
What would be the punishment for homeowners that shoot armed intruders into their home if that firearm was supposed to have been given up or seized?
(look to what has happened to some homeowners in the U.K.)