Visiting Israel, I’ve been peppered with questions from Israelis and Palestinians about where their peace process will fit in among President Obama’s priorities. My guess, I’ve answered, is that President Obama has three immediate priorities: banks, banks and banks — and none of them are the West Bank.

That said, once Obama is able to think afresh about the Middle East, he will find that the Bush team has left an interesting legacy here: 140,000 U.S. soldiers doing nation-building in Iraq and one U.S. soldier — actually a three-star U.S. Army general — doing nation-building in the West Bank. We need a better balance.

Those U.S. soldiers in Iraq can take pride in the recent Iraqi elections, which have strengthened the more secular and centrist parties. But we have to wait and see if the losers in this election take their defeat peacefully and whether the winners can actually produce better governance. The Iraqi elections, though, are a rare example of Arabs getting a chance to build their own future from the bottom up, and I continue to root for them.

Palestinians need the same chance. You can’t have a two-state solution without two states, and today the Palestinian Authority in the West Bank, which still supports a two-state deal, doesn’t have the institutions of a state, particularly an effective police force. Therefore, my hope is that Obama will focus not only on peace plans from the top down, but also on institution-building from the bottom up. The best way to isolate Hamas in Gaza is to build the Palestinian Authority in the West Bank into a decent government with steadily expanding control over its territory.

That’s exactly what the one U.S. Army officer in the West Bank, Lt. Gen. Keith Dayton, is up to. I accompanied him and his little team to Jenin — once the most violent city in the West Bank — to see their work. It was quite a scene: I watched a company of newly trained, proud and professional-looking Palestinian Authority troops, standing at attention, AK-47 assault rifles at their side, listening with obvious respect to the American general telling them: “What you’ve done has done more to advance the Palestinian national project than anything else ... You took care of your people at a difficult time. That is how the security forces of a country behave.”

No, you don’t see that every day.

General Dayton was addressing the Second Special Battalion of the Palestinian National Security Force, or N.S.F. It was trained by the Jordanian police in a program overseen by the U.S. Security Coordinator — a k a Dayton. He was originally assigned to help reform Palestinian security by the Bush team in 2005, but only got the funds to do so after Hamas took over Gaza in 2007. Some 1,600 Palestinian N.S.F. troops have since graduated, and 500 are now in training. Schooled in everything from riot control to human rights, the N.S.F. is the only truly professional force controlled by the Palestinian president, Mahmoud Abbas.

The Israeli Army, originally dubious about the Dayton mission, has come to respect it and is now allowing it to expand to Hebron. What really got Israel’s attention was that during the three-week Israel-Hamas war in Gaza, the West Bank never blew up, largely because N.S.F. troops allowed widespread protests but kept Palestinian demonstrators from clashing with Israeli soldiers.

“General Dayton is our friend,” said Col. Radi Abu Asida of the N.S.F. “Now we have excellent training. Now we have professionalism in our security work. We told the people during the Gaza demonstrations, ‘You can protest, but you must do it in a modern way.’ ”

Unfortunately, funding for Dayton’s work — secured by two farsighted U.S. House members, Nita Lowey and Gary Ackerman — runs out soon. That would be a tragedy. Before the N.S.F. was deployed “there was chaos here,” said Mohammed Abu Bakr, a Jenin wedding shop owner, referring to the security vacuum after the collapse of the Arafat regime. “Everyone wanted to fight with everyone else. Now everything is organized.”

The Dayton mission — a rare bright spot in a broken landscape — is the ground floor we need to build upon. “The issue is not just territory, but how we fill that territory,” said Gidi Grinstein, the president of the Israeli think tank, the Reut Institute. “Jenin is important. This is the beginning of capacity-building, which leads to institution-building, which leads to state-building, which leads to independence.” But the legitimacy of the Palestinian police depends on the peace process moving forward and Palestinians being ceded control, by Israel, over more territory as they prove themselves, he added. “Otherwise, they are seen as a tool to promote the occupation and will be delegitimized and attacked.”

So it is important to have George Mitchell, the U.S. special envoy to the Middle East, steadily pushing the diplomacy from above, but nothing will happen without vastly increasing U.S. efforts from below to help West Bankers build a credible governing capacity. Do that, and everything is possible. Don’t do it, and nothing is possible.