Welcome to America!
I live in a country where anyone can go to a gun show and buy a weapon without a background check. As you can expect, pretty regularly someone takes a gun to a school, a theater, a church--anywhere people gather--and shoots a lot of people. In fact, according to many reports a mass shooting happens every day; we just don't hear about it unless more than six or seven actually die.
I also live in a country where presidential candidates are suggesting that we intern Muslims because a few Europeans have shot and killed 130 people with illegal weapons they managed to smuggle in from, most likely, Libya.
Ironically, those same Europeans could have, provided they weren't on a watchlist, flown to the United States and bought their guns legally. And even if they were on a watchlist, they could still buy guns here from a private seller or from a gun show without so much as a background check.
Now, there is some evidence that at least some of these particular terrorists were on the no-fly watchlist (officials don't say exactly who's on it, for security reasons). Others may have been on a larger watchlist which has some 1.1 million names, including alternate spellings, and still others may not have been on any restrictive list whatsoever, in which case flying to the United States would have been easy: citizens of European countries don't need a visa to enter the US, and Americans don't need a visa to enter European countries.
So yes, those Europeans could theoretically have flown to the United States and purchased weapons at a weekend gun show. I'm not going to pretend to know my AK-47s from my Bushmaster rifles but I do know that Adam Lanza used a Bushmaster to kill a classroom full of first graders and some teachers. I suspect some committed terrorists would find it perfectly adequate for their purpose.
Meanwhile, the politicians who've sworn an oath to the constitution continue to talk about unconstitutional religious tests as a requirement for refugees coming to the US, while many of them want to ban Syrian refugees altogether.
But not a one has proposed tightening gun laws that have loopholes so huge that the term "law" hardly applies.
It's very hard for me to take any of their talk of "fear" seriously when they aren't willing to take the basic steps to keep me and my family safe. Right now, there's a college in Maryland that's closed until the end of the month because one of their students is missing and he has a gun.
This is the definition of terror--students unable to go to school because a bad guy, who was formerly a good guy, has a gun and is upset.
Our American terror has nothing to do with religion and everything to do with a faulty interpretation of the Second Amendment to the Constitution. We can intern all the Muslims we want and build a wall high enough to keep out migrants and prevent every single asylum seeker from reaching our shores, but we'll still be forced to live in terror.
But it's the kind of terror that Americans are remarkably willing to put up with.
Welcome to America. Here's your gun, and a copy of our constitution. Ignore everything in it except a few words in the Second Amendment.