Since the election of relative moderate Hassan Rouhani to Iran’s presidency, there’s been a wave of events producing a newfound optimism about the prospects for a peaceful resolution of the dispute over Iran’s nuclear program. President Obama sent a letter congratulating Rouhani on his victory and mentioning other, unspecified issues, and Rouhani reciprocated. Obama told Telemundo he saw Rouhani as “somebody who is looking to open a dialogue with the West, and with the United States, in a way we haven’t seen in the past. And so we should test it.”

Iran’s Supreme Leader, Ali Khamenei, got into the act, reiterating an earlier call for “heroic leniency” in diplomacy over the nuclear program. Khamenei also told the radical and anti-American Islamic Revolutionary Guards Corps to butt out of Iran’s politics. At this time of writing, there are reports Tehran has released a number of political prisoners in Iran.

It all adds up to a period of positive trends in relations between the two countries. But it’s important not to overlook the fact that while atmospherics may help bring about talks, the countries are miles apart on the substantive issues surrounding Iran’s nuclear program. Too much attention has been spent on getting to talks, and too little on bridging the chasm dividing the parties.

A central, if not the central, problem is that the American foreign policy community has failed to lay out any conceivable way Iran could satisfy Washington other than immediate suspension of all uranium enrichment with no serious sanctions relief in return, which nearly everyone agrees isn’t going to happen. Congress seems to have two speeds on Iran policy these days: sanctions and asleep. Congress regularly piles on more sanctions to Iran, some painful, some symbolic, because it’s the easy thing to do politically, and no one seems willing to spend the political capital to provide Iran with a realistic offramp by which Tehran could lessen the pain and save face. Unfortunately, Congress’ actions and rhetoric have given the Iranians good reason to fear that our real policy in Iran is regime change, which can’t augur well for a deal.

Adding to the problems, Israeli Prime Minister Benjamin Netanyahu recently reiterated his own ultimatum to Iran, which is certain to fail. Netanyahu, whose hawkish id commands more influence in Washington than one might hope, demands zero enrichment in Iran—a formula no one believes is achievable. This formula puts Israel, and likely the United States, on a path to war with Iran.

So would Sen. Lindsey Graham, who last weekend reiterated his call for Congress to pass a war resolution allowing the Obama administration to bomb Iran when it determines bombing would be appropriate.

To be fair, however, the Washington debate has moved decidedly in the direction of common sense since the Iran nuclear issue first heated up in 2006. The intelligence community, in 2007 and 2011, concluded that Iran has not yet taken the decision to push for a nuclear weapon, and that Iran’s calculus on this matter was responsive to external events, including U.S. policy.

And mainstream commentary has inched away from assertions that suicidal mullahs would launch unprovoked nuclear strikes at Israel. Claims that Iran would give nuclear weapons to terrorists have faded. And the argument that a nuclear Iran would precipitate a cascade of nuclear proliferation has faced steady opposition from academic researchers and now a sharp blow from the Center for a New American Security, an establishment think tank.

Iran might be lying, but it looks more inclined to say yes to a reasonable nuclear deal than it has in the past 10 years. If U.S. political leaders care as much about the Iran problem as they say they do, and if they’re really looking to avoid another counterproliferation war, that fact should push Washington to swallow its pride and offer a more realistic deal than it has been inclined to do until now.