CNS News has a pretty good moment here for Barack Obama from yesterdays’ presser with Mexico’s President Felipe Calderon, after a reporter from Mexico challenged Obama on why he doesn’t just “veto” the 2nd Amendment. Obama patiently explains that American Presidents have to work within the Constitution and don’t have the power to veto its provisions, and then explains that the 2nd Amendment isn’t the problem in gunrunning between here and Mexico. We can and should curtail that through enforcement of existing law, Obama says, rather than infringing on the “legitimate” uses of firearms by American citizens:

“The Second Amendment of the United States Constitution allows American citizens to carry weapons and this principle is defended,” the Mexican reporter said. “However, President Calderón has said that this law in Congress–this could actually go against U.S. agents, and this has happened. So, President Obama, in Mexico we have the veto, the power of veto. I don’t know how far you have the ability to veto that law that has been approved. And if you have that responsibility, why don’t you do so, sir? How long are we going to allow Mexicans to be murdered–and not just Mexicans, but now Americans, as well?”

Obama responded: “Well, the Second Amendment in this country is part of our Constitution, and the president of the United States is bound by our Constitution. So I believe in the Second Amendment. It does provide for Americans the right to bear arms for their protection, for their safety, for hunting, for a wide range of uses. That does not mean that we cannot constrain gun-runners from shipping guns into Mexico. And so we believe that we can shape an enforcement strategy that slows the flow of guns into Mexico, while at the same time preserving our Constitution.”

Of course, we would need the ATF to stop expediting the flow of guns first before attempting to interdict them, as one ATF agent accuses the agency of doing:

An Alcohol, Tobacco and Firearms senior agent assigned to the Phoenix office in 2010, Dodson’s job is to stop gun trafficking across the border. Instead, he says he was ordered to sit by and watch it happen.

Investigators call the tactic letting guns “walk.” In this case, walking into the hands of criminals who would use them in Mexico and the United States.

Dodson’s bosses say that never happened. Now, he’s risking his job to go public.

“I’m boots on the ground in Phoenix, telling you we’ve been doing it every day since I’ve been here,” he said. “Here I am. Tell me I didn’t do the things that I did. Tell me you didn’t order me to do the things I did. Tell me it didn’t happen. Now you have a name on it. You have a face to put with it. Here I am. Someone now, tell me it didn’t happen.”

Agent Dodson and other sources say the gun walking strategy was approved all the way up to the Justice Department. The idea was to see where the guns ended up, build a big case and take down a cartel. And it was all kept secret from Mexico.

ATF named the case “Fast and Furious.”

In defense of the ATF, I’m not sure I’d bet on the ability of Mexico’s security forces to keep a secret. But it’s hardly clear that “gun walking” would provide a boon of information to take down one of Mexico’s cartels. Instead, it just seems to have allowed the cartels to arm themselves a little more cheaply than otherwise. After the murder of an American border agent — which should be a high-profile investigation — the provenance of the weapon doesn’t appear to have given the US or Mexico any better leverage against the cartels at all.