Israel’s interdiction on March 5 of an alleged Iranian weapons shipment bound for Gaza has no doubt increased Congress’s skepticism of the Obama administration’s diplomatic engagement with Iran.

Iranian Foreign Minister Javid Zarif’s reaction to the weapons seizure was also not helpful. Rather than calling for an investigation, as he should have done, he accused Israel of chicanery in an effort to sabotage the nuclear talks.

Israeli officials in turn pointed the blame at the Rouhani administration without substantiating their accusation. The charge would probably be more accurately directed at the Revolutionary Guard, which still answers to Supreme Leader Ali Khamenei, not Hassan Rouhani.

Rather than interpreting this incident as further evidence that the Iranian government is incorrigibly duplicitous, Congress should remain cognizant that there is a quiet but ongoing tug-of-war over the direction of Iran’s foreign policy between the relative moderates in the Rouhani administration and the hardliners outside of it. Keeping this internal political dynamic in mind, they should work to strengthen the credibility of the moderates as well as persuade the hard-liners that they stand to benefit more from compromise than confrontation.

The first step is to convince them that the United States is not an implacable threat but rather that U.S. actions against Iran are motivated by the United States’ threat perception of its behavior. The second is to convince Iranian leaders to cease or moderate actions and rhetoric that contribute to this perception. The third is to offer them substantive incentives for taking these political risks.

In parallel but not dependent on the nuclear negotiations, Congress should specifically signal a willingness to support a U.S.-Iran dialogue on the terms of a just solution to the Israeli-Palestinian conflict — a cause the Supreme Leader Khamenei has championed for decades.

President Rouhani has expressed a willingness to accept a two-state solution accepted by the Palestinians and has sought to renew ties with moderate Palestinian leaders but Khamenei, who retains authority over Hezbollah, has not endorsed the two-state model. Khamenei reportedly did approve a letter to the Bush administration in May 2003 expressing a willingness to negotiate on it however. If the Supreme Leader could be convinced to order Hezbollah to moderate its political objective to achieving this outcome, it would send a powerful signal to Israeli officials that the prospect for peace with Iran exists.

Khamenei’s animus toward Israel is based on his view that it seeks to forcibly expand its territory and dominate the Muslim world economically and that it will continue to act with duplicity toward the Palestinians with the implicit backing of the U.S.

The United States needs to demonstrate that it is an honest broker and present Khamenei with the opportunity to compromise in the interest of the Iranian people as well as his own legacy. If he could be persuaded to entertain the possibility of a greater long term vision of justice for the Palestinians than the forcibly imposed one-state solution he has envisioned, there is a possibility that he would choose to explore it.

Congress should also not preclude the possibility of Iran continuing its democratic evolution as its threat perception of the outside world continues to subside. Policymakers should focus on opportunities for détente that could have positive security effects for the U.S. as well as Israel, Lebanon, Syria, Iraq and Saudi Arabia.

It is easy to disdain the prospect of moderation in Iran-Israel relations — just as it was to disregard the idea of a diplomatic breakthrough between the U.S. and Iran less than a year ago and an Arab peace initiative with Israel in 2002. In the interest of the security of the United States and Israel, Congress should offer bipartisan support for open dialogue between the U.S. and Iran on a just solution to the Israeli-Palestinian conflict.

Thomas Buonomo is a former U.S. Army Intelligence Officer and specialist in Middle East affairs.