In the last three years, the United States has tripled the number of troops in Afghanistan, increased the number of drone strikes in neighboring Pakistan, and killed Osama bin Laden—the highest of high-value targets. President Barack Obama has more than enough victories under his belt to stick to his timeline and substantially drawdown the number of troops from Afghanistan.

Still, the pace of America’s withdrawal and the size of its residual combat presence, even after his decision Wednesday, will depend on two things: negotiations with the Taliban and political pressure to stay the course. These two factors will feature prominently in the months ahead, as the administration reconfigures the strategy and objectives for winding down the 10-year campaign.

First, although many Afghans endorse engagement with the Taliban, in Washington, even broaching the subject of talks is divisive. Secretary of State Hillary Clinton confirmed that efforts were under way to negotiate with the Taliban; meanwhile, outgoing Secretary of Defense Robert Gates said he believes the Taliban will not engage in serious talks until they are under extreme military pressure. In a way, both are right: a power-sharing arrangement would provide the best hope for sustainable peace, but no treaty, agreement, or contract is self-reinforcing and thus requires some leverage. Either way, constructive, face-to-face talks with senior Taliban leaders will be an intensive process, and one that diplomats and military officials must be prepared to defend publicly. America is not there yet.

The second force that will temper America’s eagerness to withdraw is the power of domestic political pressure. Defense Secretary Gates, Senator Lindsay Graham (R-SC), House Intelligence Chairman Mike Rogers (R-AL), and a sizeable contingent of Afghanistan hawks in the media decry anything less than a troop-intensive campaign. They endorse slow-paced, graduated troop cuts subject to conditions on the ground, a policy focused on entities other than those that threaten the United States. Dismantling al Qaeda, an outfit already in disarray, calls for counterterrorism, not state-building. This can be done relatively cheaply and with far fewer troops. Moreover, as seen in Yemen and Somalia, the United States can collect actionable intelligence without a large-scale conventional force on the ground.

Whether it is talking with the Taliban on the one hand, or staying the course on the other, the president has political goals, for which there is no clear strategy, and security progress, for which there is no definitive “victory.” Looking back, however, Obama has achieved some of the goals he set out. “Blueprint for Change,” his 2008 presidential campaign literature, states (pdf):

Obama will fight terrorism and protect America with a comprehensive strategy that finishes the fight in Afghanistan, cracks down on the al Qaeda safe-haven in Pakistan, develops new capabilities and international partnerships, engages the world to dry up support for extremism, and reaffirms American values.

To a certain degree, even these goals are ambitious. Instead, he should focus not on what is politically desirable, but what is within America’s ability to accomplish. In this respect, Obama would do well to revisit his December 2009 speech on the war in Afghanistan, when he said:

We’ve failed to appreciate the connection between our national security and our economy. In the wake of an economic crisis, too many of our neighbors and friends are out of work and struggle to pay the bills. Too many Americans are worried about the future facing our children. Meanwhile, competition within the global economy has grown more fierce. So we can’t simply afford to ignore the price of these wars.

He also said:

Indeed, some call for a more dramatic and open-ended escalation of our war effort—one that would commit us to a nation-building project of up to a decade. I reject this course because it sets goals that are beyond what can be achieved at a reasonable cost, and what we need to achieve to secure our interests…America has no interest in fighting an endless war in Afghanistan.

As U.S. forces eventually take a back seat in Afghanistan, Obama should strongly resist any calls that he has not done enough. Arguably, he has gone above and beyond what would have been a more prudent strategy. Now, it is time to come home.