If you tighten gun laws within a 100 mile radius of the border, criminals will buy guns to be smuggled across at shops located 150 miles from the border. If it becomes difficult to buy guns in Yuma, the criminals will go to Phoenix. When it becomes difficult in Phoenix, they'll go to Flagstaff. When it becomes difficult in Flagstaff, they'll go to Utah, and so on, and so on.
Restrictive gun laws in New York City haven't stopped firearms from being brought into the city - it's merely given rise to another criminal act, that of gun smuggling.
From the New York Times --
This is what you and those of your ilk fail to acknowledge - the more something is prohibited (drugs, alcohol, firearms), the more the criminal element not only desires it, but is willing to go to greater risk to obtain, and possibly financially profit from it. Prohibition gave rise to the organized crime element that still plagues us to this day.Eight current and former New York Police Department officers were arrested early Tuesday on federal charges including gun trafficking and conspiracy to smuggle cigarettes, according to people briefed on the case.
A quick anecdote -- Recently I had a head cold, and stopped in a store in another state to buy some Actifed. Because I was an out-of-state resident, I was not able to purchase Actifed because it contains pseudoephedrine - the main chemical used in making crystal meth. I have no desire to use meth, I am not a "smurf" who buys Actifed and resells it to people who make meth - I'm merely a traveler with a head cold. But, because of the failure of the government to regulate sales of this pharmaceutical, I have to suffer.
Which brings me back to my original point - why does the farmer in North Dakota have to suffer because of the failure of the government to stem gun flow across the Mexican border?