There once was a time when President Obama implied that the Afghanistan war would at least start to end in July 2011. Then that date got pushed back to 2014. Now, the general in charge of training Afghan forces to take over for departing Americans pegs that date closer to 2016 or 2017 — that is, if the U.S. doesn’t want the entire Afghan security apparatus to implode.

What will ensure Afghan soldiers don’t collapse? “Strategic patience and an enduring commitment,” Lt. Gen. William Caldwell told a crowd at the Brookings Institution in Washington. Translated from the mil-speak: many more years and billions of dollars. Asked by Danger Room how much longer the training mission needs to last, Caldwell replied, “We won’t complete doing what we need to do until about 2016, 2017.”

It’s one thing to train Afghans to fight. Lt. Gen. William Caldwell has done that in spades, producing an “industrial kind of method” to build a force of 296,000 soldiers and cops — more than 100,000 more than when he arrived in Kabul in fall 2009. But the real test for the training mission is “that it endures and it will last,” Caldwell said. “It has to last. It’s not enough to just transition.”