They would allow the U.S.-based associates of a Mexican drug cartel to continue acquiring firearms uninterrupted. In doing so, they hoped the weapons, after they were recovered at crime scenes in Mexico, could be traced and linked to cartel operatives including possible high-level financiers, suppliers, and possibly even king-pins.
My question is, "To what end?" What good does it do to link a weapon, known to have been bought in the US and recovered at a crime scene in Mexico, with a king-pin? That doesn't make the king pin any more convictable. It doesn't make the straw purchacer, who you had and then let go in the US, and more convictable. It doesn't help Identify the king-pin.
Unfortuantely, the only conceivable utility for the gun walking plan, with no attempt to follow the weapons -- just wait for them to turn up at a crime sceme and a trace request to come in from MX -- is for political anecdotal support for ill-conceived gun control laws. The local agents don't benefit from that -- unless they get some personal gratification from narrowing the rights of Americans. The only political appeal for such a plan is higher up the ladder. There HAS to be some paper trail evidencing that. Hmmm . . . Wonder why exec privilege has been asserted for the documents subpoenaed?