President Obama had little choice but to float the threat of the “zero option” to Afghanistan President Hamid Karzai.

Karzai’s stubborn refusal to sign the bilateral security agreement that would allow troops to stay in Afghanistan is wrongheaded and dangerous.

If the United States is forced to withdraw its troops by the end of the year, the Taliban and al-Qaida will almost certainly fill the power vacuum. The Afghan army is not ready to take over the country’s security, which is why U.S. officials want to keep as many as 10,000 troops in Afghanistan to train those soldiers.

Nearly 3,500 coalition troops, mostly American, have been killed in the 13 years of war. From that sacrifice, al-Qaida and the Taliban have been severely damaged. Pulling out now would undo much of that progress. Still, the outgoing Afghanistan president is forcing the United States to plan for a pullout this year.

The White House is aware that it will soon be dealing with Karzai’s successor, and the major candidates for president have all signaled that they would sign the security agreement. But who’s to tell?

As reported in the New York Times, of the 11 parties represented in the April 5 elections, six include at least one candidate on the ticket who is widely considered to be a warlord.

Withdrawing our troops in the next 10 months should not be the way forward, and not only because it will be a logistical nightmare and invite a return of the Taliban and al-Qaida.

The move could further destabilize the region if India and Pakistan, nuclear-armed neighbors who have fought each other before, enter a proxy war in Afghanistan in a bid for regional influence.

It should be of no surprise that neighboring countries want the troops to stay. All 11 of the presidential candidates vying to succeed Karzai want some American troops to stay. The Afghan military wants them to stay. Everyone is on board, it seems, except Karzai.

With Karzai continuing to spew anti-American rhetoric, he leaves the Pentagon no option except to start planning a pullout, and hope the next president listens to reason.