When President Obama addressed the nation about Thursday's (Oct. 1) mass shooting at Umpqua Community College in Roseburg, Oregon, his emotions ran high.

"Somehow this has become routine," he said. "The reporting is routine. My response here at this podium ends up being routine ... And what's become routine, of course, has been the response of those who oppose any kind of common sense gun regulation."

Earlier on Thursday, presidential candidate Ben Carson took to the radio to deliver one such routine response. In the process, he promoted a dangerous falsehood that gets repeated nearly every time we have a mass shooting in this country -- that is, it's not guns but rather the mentally ill we should really be worried about.

“Obviously there are going to be those calling for gun control, but that happens every time we have one of these incidents," Carson said during his interview on the Hugh Hewitt Show. "Obviously that’s not the issue. The issue is the mentality of these people. And we need to be looking at the mentality of these individuals and seeing if there are any early warning clues that we can gather that will help us as a society be able to identify these people ahead of time."

Carson seems to be suggesting that keeping tabs on every mentally ill person is a better idea than keeping tabs on guns.

“What I worry about is when we get to the point and we say we have to have every gun registered, we have to know where the people are and where their guns are," he continued. "That is very dangerous, that I wouldn’t agree with at all.”

But as American Psychiatric Association President Dr. Renee Binder pointed out last time we had to have this conversation, "Most people who suffer from mental illness are not violent, and most violent acts are committed by people who are not mentally ill. If you look at that large pool of people, only a tiny proportion of them will eventually commit violence. How are you going to identify them? It's like a needle in a haystack."

That's not an exaggeration. Nearly one in five Americans has experienced mental illness, yet the stigma around such illness can still be devastating -- especially if it stops the people who need it most from seeking treatment.

Besides, as Newsweek reported this morning, "efforts aimed at keeping the mentally ill from guns have done little to lower the overall crime rate."

Newsweek's report went on to explain that "in 2001, Connecticut added patients who had been involuntarily committed to mental institutions to the National Instant Criminal Background Check System. The result? Violent crime among those persons dropped by over 50%, but since they constitute such a small percentage of the criminal population, only 14 violent crimes were prevented -- not 14 mass shootings, just 14 violent crimes."

Additionally, a 2001 study of young male mass murderers found that only 23% of them -- or one in four -- had ever received any sort of mental health treatment or diagnosis. That means that even if we did elect to focus all of our reform efforts on mental health instead of gun law reform, it would likely do little in the way of preventing these sorts of crimes.

“If we were able to magically cure schizophrenia, bipolar disorder and major depression, that would be wonderful," Dr. Jeffrey Swanson, a professor of Psychiatry at Duke, said in an interview with ProPublica last year. "But overall violence would go down by only about 4%.”

Obama noted during Thursday's address that while the individuals behind these crimes have "a sickness in their minds," the United States can't blame the number of mass shootings solely on mental illness.

"We are not the only country on earth that has people with mental illnesses who want to do harm to other people," Obama said. "We are the only advanced country on earth that sees these kinds of mass shootings every few months."

If we want this to stop, "we're going to have to change our [gun] laws," Obama added. "And this is not something I can do by myself."