Afghans went to the polls Saturday, but results won’t be in for at least another two weeks. If none of the candidates wins a majority of votes (the most likely scenario), a run-off election will have to be held probably in late May or early June.

The Taliban did their best to deter voting and undermine the electoral process in Afghanistan.

In the weeks running up to the election, they attacked international election observers at a Kabul hotel, the Independent Election Commission office, and numerous Afghan candidates and election workers. On the day of the election, there were some 140 attacks or attempted attacks throughout the country.

Yet Saturday’s elections saw a higher-than-expected turnout —perhaps 60 percent—which demonstrates that Afghans want democracy, not the harsh Islamist rule on offer from the Taliban.

American support for the war in Afghanistan is abysmally low at less than 20 percent. Reports of widespread Afghan government corruption, the persistence of Taliban safe havens in Pakistan, and President Karzai’s ranting against U.S. policy have led to calls for the U.S. to end the mission there altogether.

But Saturday’s elections should restore a measure of optimism about Afghanistan’s future. The high turnout in the face of Taliban threats and violence should remind Americans why the U.S. went to war in the first place and what’s at stake if we give up on the mission prematurely.

Despite President Hamid Karzai’s refusal to sign the Bilateral Security Agreement (BSA) spelling out the parameters of a residual U.S. force presence post-2014, most Afghans want international troops to remain in the country. Nearly all of the eight presidential candidates said they will sign the BSA if elected and 2,500 local tribal leaders voted in favor of the BSA last November.

U.S. Commander in Afghanistan General Joseph Dunford has said at least 10,000 U.S. troops will need to stay in the country after this year to backstop, train, and advise the Afghan forces and help them consolidate gains against the insurgents.

A new Afghan government – which may take time to get in place given the likelihood of a run-off election – must act quickly to sign the BSA. Otherwise U.S. funding for Afghanistan will be at risk. The U.S. Congress already slashed funding for Afghanistan by 50 percent in January because of Karzai’s unhelpful policies.

This election and continued U.S. engagement in the country is particularly important for women and ethnic minorities. Unlike when the Taliban ruled the country and prevented women from attending school, let alone participating in the politics and economic life of the country, one of the election candidates, Zalmay Rassoul, included a woman vice president on his ticket.

The other two top presidential contenders, former Afghan Foreign Minister Dr. Abdullah Abdullah and former Afghan Finance Minister Dr. Ashraf Ghani Ahmadzai, also are committed to democratic values and experienced in dealing with western officials.

Whereas the 2009 elections were severely marred by allegations of vote rigging and left both Afghans and the international community in doubt about the viability of democracy in the war-torn country, Saturday’s elections have dealt a blow to the Taliban and restored confidence that Afghanistan can avoid slipping back into chaos.

There will inevitably be some claims of voter fraud. And, if no one candidate gets 50 percent of the vote, it will be expensive and dangerous to hold a second round of polling, Even when the new government is established, it will face the same challenges of the last 13 years.

However, there is no doubt that Afghanistan took a step forward on Saturday.

Now is not the time for the U.S. to give up on the Afghan mission and turn its back on the country. Instead, it should reinvigorate its commitment to fund and train the Afghan security forces. The White House should also state clearly its commitment to leaving a substantial troop presence of at least 10,000 forces, assuming the new Afghan President signs the BSA.

While Karzai’s position on the BSA was irresponsible and unforgiveable, the Obama administration also sent mixed messages on the number of troops it was prepared to leave behind.

The global terrorist threat is evolving, not dissipating. It is vital that the U.S. work to prevent a Taliban resurgence.

The Afghans have demonstrated their determination to build a democratic country and willingness to defy the Taliban in doing so. The U.S. must show it is fully behind them.

 - Lisa Curtis is a senior research fellow in The Heritage Foundation’s Asian Studies Center.