@Ms Spock You know that I care about you, and certainly don't want to get into an argument with you on this.
As to your question; there have been incidents of mass homicides in other countries where guns were not used.
One of the most horrific mass homicide with a gun was in Norway, where gun laws are very restrictive.
As for this country, there are many reasons that we have seen mass homicides take place, and in almost every situation it was a guns free place; a place where the gunman knew he could go to without fear of retaliation.
I think to understand the American's strong stand on gun ownership you have to go back to the constitution and the American Revolutionary war.
Our founding fathers lived in a time where the British government tried to take guns away from the citizenry so they could continue to commit their unjust actions toward the colonist.
When the war ended and the colonies formed the first government, ( A confederacy) it did not enjoy much success, so in 1789 the founding fathers convened the first constitutional convention which created our present form of government; giving much more power to the federal government.
A majority of the state representatives and the founding fathers would not ratify the constitution unless specific fundamental rights were included in the constitution. Those rights became known as the bill of rights.
The second amendment, the right to bear arms, was specifically added to give the citizens the right to defend themselves against tyranny, should this newly empowered central government become tyrannical.
We the citizens maintain that gun ownership gives us that check and balance against the government taking from us our guaranteed rights, and trust me it is becoming more and more evident that our government would love to reduce or eliminate our right.
The recent Supreme Court Judgement regarding gay marriage is going to be, and is already being used to undermine or 1st amendment right, the freedom of religion. the Chief Justice, Roberts, who descent-ed on the vote has already told fundamental churches that they will lose their tax exempt status unless they perform same sex marriages. While you may agree with gay marriages, many of the churches disagree, for religious reasons, and have already been told by our president that we must change our religious beliefs to accomidated this new constitutional right.
I only bring up the decision of the supreme court to show you how the government wants to reduce our rights as citizens of this great country and take control of our lives. This is why the second amendment is so important to us.