Why would criminals go through the trouble and risk of all that travel when they could simply "one-stop-shop" i.e. commit their crimes where they buy the guns. Might it be that they just might be aware that others in that "lax" area might have guns as well?
Of course, the trends support a robust concept of armed self-defense. In the past couple decades, 40 states have passed right-to-carry laws. Many to most have seen crime decreases, and not one has seen an increase.
But, gun control is one of those topics where liberal orthodoxy and their version of "common sense" trumps empirical data and history. The gun-banners "know" that allowing greater access to guns is certain to create crime, to turn the law-abiding into macho vigilantes, to prompt "old-west" style shootouts, and to greatly spike the number of people killed by their own guns. They "know" and argue these points by claiming that they're obvious - forget the facts or the statistics (which they dismiss either by attacking the source, declaring without evidence that they've all been fudged, or declaring (again, without evidence) that they *could* just as easily find stats that support their positions).
This reminds me of an old gag from college math and science classes - you start solving the problem, then write the answer and claim that it's "intuitively obvious." Too bad professors don't give credit for "intuitively obvious."
The problem with all the gun control laws and statistics is that there's really no null hypothesis. If guns were banned in total, 100% of the crimes would be committed by illegal gun owners. If there were no gun control laws, 100% of the crimes would be committed by legal gun owners.
Human behavior has far more to do with it than anything else. If a criminal seeks to accomplish something, he's going to do it if motivated enough. However, guns can deter a spontaneous event, I believe.
Long story short, guns in the hands of the responsible will either do no harm or possibly help. Guns (or anything else for that matter) in the hands of the irresponsible and criminal element will do no good or do harm.
To me, that is the simple truth about gun control. It's government trying to fix a problem, except the problem is a symptom and not the source of the problem to start with.