Of course there is no empirical evidence, the NRA and the GOP have worked really hard to make sure we can't study the issue. I covered this clearly above. Saying "there is no evidence" when the gun lobby works as hard as possible from stopping anyone from looking for evidence is a farce. "We can't do it anyway, it's just a meme." But all evidence is to the contrary.
It worked with machine guns. It worked with ammonium nitrate. It worked in every other country that has tried it. All of those institutions still have "huge cracks" but it has cut way, way back on crimes committed with the regulated items.
Right now there are 250,000 automatic weapons in private hands all over in the USA. How often are they stolen and used in crimes (the answer: in the last 80 years there have been 2 murders with machine guns)? How often are they bought by straw men and used in crimes? How often does a farmer buy 1500 pounds of ammonium nitrate and give it to a right wing nationalist?
There certainly will be cracks. In the short term it will do almost nothing. In the long term, nothing indicates it wouldn't work. Other than the fact we won't bother trying.
So sure, other than the fact it usually works when we try, there is no evidence saying it will work.
Regulation of semi-auto long guns might sound like a good idea but it is a false sense of security. If one tool is eliminated, terrorists will find another way to do it. Out of the 25 worst acts of terrorism in human history, 80 percent involved or exclusively used explosives, at least according to this list:
http://list25.com/25-worst-acts-terrorism-committed/1/Another was carried out with daggers, yet another reign of terror was committed with the guillotine.
It’s on the internet, so it has to be true.
The guns are merely the tool of a sick or angry mind. If someone wanted to kill 30 school kids they can bomb a school bus or drive a semi-truck into the playground of a school. There is no shortage of places in large US cities where a car bomb could take out 50 to 100 people during peak rush hour in the city center or detonate one as thousands of people are leaving a major sporting event or concert.
Look how easy it was for the bombers to set off a bomb at the Boston Marathon. We can assume what has kept that from happening again or at another large marathon is a heightened awareness of security and a stepped-up security presence, not a ban on pressure cookers or back packs. Again, terrorists are usually not looking for resistance. They look for a target-rich environment with minimal to no security where people would least expect an attack to occur. Who would have ever thought a gay nightclub would be the stage for a savage attack like that?
Perhaps an investment in more police or military presence in major cities is what we need to prevent terrorist attacks, which are still quite rare in the United States. Perhaps school districts take the threat serious enough, they have more armed guards at every school. Perhaps nightclubs will employ armed guards. Are we really frightened enough to say we’d rather invest money earmarked for roads on more cops and more security? Whoops, no can’t have more police or military on US streets, that’s tyranny!
We are Americans, we suffer from a short attention span. If more police presence or better security sounds like a better idea today, we will assume everything is okay in a few weeks and won’t vote to spent the money on more cops or security when the time comes.
Estimates range from 4 million to 30 million semi auto rifles in the U.S. Crime statistics would tend to indicate over 99% of those weapons are owned by responsible people who have no intention of carrying out a mass shooting. So we stop the manufacture and sale of any of these types of guns now. What happens next? Do we institute a government hand-over (will never happen as that would be seen as tyranny and the dis-arming of citizens) or buy back?
Let’s be honest, if semi-auto long guns did not exist, terrorism would not cease to exist.
Perhaps time would be better spent analyzing and implementing better counter-terrorism measures instead of taking the simplistic approach of banning
a weapon which is used in a very small percentage of terrorist attacks. This is a very complex problem which goes far beyond semi-auto rifles simply existing.