The San Bernadino massacre was an interesting combination of an ideologically motivated terrorist attack and a personally motivated case of workplace violence, and it suggests something nobody's really said out loud: they don't "hate our freedom;" they hate us.
The Farooks had a substantial arsenal in their town house, considerably more than they needed to shoot up a social services agency, and it may be that Nicholas Thalasinos, one of the victims, saved many lives by pissing off Syed Rizwan Farook in an argument a couple of days before the incident. Thalasinos, a Jew (in his official "victim" photo, he's wearing a tallis) with an unlikely Greek name is said to have been extremely pro-Israel and, it seems safe to say, not favorably inclined towards Muslims. We don't know the specifics of the argument yet, but we can easily imagine its tenor. Were it not for Thalasinos, the Farooks might have selected a target where many more fatalities would have been possible.
We don't know if Thalasinos was a Republican, but we can be fairly certain he sounded like one. You don't have to be a Republican to be virulently anti-Muslim these days, and Republican fear mongering cannot be without its effects. American attitudes towards fellow Americans who are Muslims can only stoke more hatred, and generate more radicalization and criminal activity. They have good reason to hate us — that is, to hate us back.
I don't believe stricter gun control laws, the Democratic response to domestic terrorism, would make much difference. California has gun control laws that are as restrictive as any in the country, and it didn't help. The kind of European-style gun control that might make a difference is politically impossible in the USofA.
As for the Republican approach to terrorism, it's just as hollow as that of the Democrats. Sending troops to Iraq and Syria to "root out" the Islamist State can only make matters worse, especially since our nominal "ally," Haider al-Abadi, says he would consider it an act of war. The idea is to have fewer enemies in the Middle East, not more.
Personally, I have no idea what policies the USofA should pursue at this time. Obama's approach, just trying not to make matters worse, seems to be as good as we can manage at the moment. Republican efforts to make matters worse as a means to win the 2016 election, sad to say, will not subside no matter what intellectual or moral appeals are made to them.
Given enough time, Islamist terrorism will be replaced by some other seemingly existential threat, but I'll probably be dead by then. I hope future generations of Americans can do better than mine has.