Exits are easy to spot when you know where you're going. This might explain why the United States is still fumbling with the locks on its way out of Afghanistan.
The US president Barack Obama's previous attempt at an Afghan war strategy promised more than this. Last year, Mr Obama settled on a surge of 30,000 US troops with a caveat: forces would begin leaving by July 2011. While critics cautioned that setting an end date might inspire the Taliban's patience, at least Mr Obama appeared committed to ending a war that by all accounts has gone badly.
"Obama is right to pull the troops out," the former Soviet leader Mikhail Gorbachev told the BBC last month, "no matter how difficult it will be." Mr Gorbachev knows Afghanistan's dangers all too well.
There was a time when the Obama administration also appeared to understand them. No longer. Washington is now planning to publicly walk back from the initial 2011 date, and is expected to pitch a new blueprint for the war effort, emphasising instead 2014 as the year that combat will end.
The White House is already comparing their altered timeline to the Bush administration's surge strategy in Iraq, where an inflow of troops preceded a draw down. "Iraq is a pretty decent blueprint for how to transition in Afghanistan," one official in the Obama administration told The New York Times.
The temptation to see Iraq as a model for fighting in Afghanistan is understandable. It is also dangerously misleading. Iraq maintained a functional government long before the US invasion in 2003, whereas Afghanistan endured decades of civil war even before 2001. Kabul needs much more non-military aid than it is getting if Washington wants to leave even a modicum of stability in Afghanistan when it exits.
There are other challenges as well. Winter typically brings a lull in fighting, but coming off the war's deadliest year, it's hard to see that the arrival of spring will provide much comfort. Meanwhile, the Taliban's control of regions that were once calm appears to be spreading. For the war effort to have any chance of success, these areas will have to be re-claimed. Greater cooperation from Pakistan is also essential.
Steps that will build confidence in America's commitment to the region are certainly overdue, and recognising that Afghan security forces need more time is welcome. But the Obama administration has still not offered a clear definition of what "victory" might look like. Moving the date for a final pullout of US troops further down the road won't answer that question. It may simply make the exit more difficult to find.