Although the Trump administration waived those sanctions again this week, as required by Congress to keep the nuclear accord intact, it added a new raft of penalties aimed at Tehran's ballistic missile program, which is not covered under the deal.
Moreover, the president's oft-stated opposition to the 2015 Iran deal — and his sweeping aside Obama administration concerns about Saudi airstrikes on civilian targets in Yemen — has the Saudis willing to overlook Trump's strident language about Muslims during the presidential campaign.
"This visit will be considered by history as a crucial turning point in opening relations between the Arab world and the West," Saudi Foreign Minister Adel Jubeir told reporters Thursday at the palatial Ministry of Foreign Affairs in Riyadh.
For his part, Trump hopes to leave the swirl of political scandals behind in Washington with the pomp of a two-day visit to a longtime ally that fulfills his vision of reasserting American power around the globe after what he considers a retreat by the Obama administration.
While recent presidents have made their debut foreign trip to Canada or Mexico, Trump wants to return the U.S. strategic focus to the Middle East, and to restore the previous American tilt toward Sunni power in the region after President Obama's so-called pivot to Asia and his outreach to Iran.
During his time in Riyadh, Trump is expected to emphasize a shared commitment to fighting
The U.S. is considering selling thousands of precision guided bombs, howitzer artillery pieces, and the sophisticated antimissile system known as Terminal High Altitude Area Defense, or THAAD, according to U.S. officials. The cost could reach a staggering $100 billion.
"This is a huge deal for the Saudis because I think they largely felt that what the previous administration had done is unleashed Iran on the region," said James Carafano, a Heritage Foundation analyst who advised Trump's campaign and transition team.
"The Saudis really look at this as a major political, diplomatic shift that puts them back on the top, and they want to do everything they can to make that U.S.-Saudi relationship seem as strong and as resilient as possible," he added.
The Pentagon has already resumed sharing certain intelligence, including satellite imagery, with the Saudi military fighting Iranian-backed Houthi rebels in Yemen's civil war, Saudi officials said.
The Obama administration had cut back cooperation with the Saudi-led military coalition after human rights groups said Saudi warplanes had bombed medical facilities and had used cluster munitions, which are banned by most countries, against civilian targets in Yemen.
The shift came in part as new domestic energy sources and technologies allowed the United States to ease its decades-old reliance on Saudi oil and gas. That reduced Saudi influence in Washington just as Obama was seeking to wind down America's military involvement in the region's wars.
But several of Trump's top advisors want to tilt U.S. policy in the Arab world back toward Sunni power, led by the Saudis, as a counterweight to Shiite Iran.
Defense Secretary James N. Mattis acknowledged what he called the "past frustrations" during a visit to Riyadh last month. He stood beside Deputy Crown Prince and Minister of Defense Mohammed bin Salman, who had visited Washington in March to meet Trump.
"I think that what is important today is that we identify practical steps as we take this relationship forward," Mattis added.
Trump, who heads to Israel after he leaves Riyadh on Monday, could claim a significant diplomatic victory if he can nudge the two countries to make mutual gestures toward ultimately normalizing relations.
Michael Oren, a former Israeli ambassador to Washington who how is a deputy minister for diplomacy, said mutual antipathy toward Iran could be the key.
"Today, Israel and the Sunni Arab states have a greater confluence of interests than at any time since Israel's creation," he said.
Saudi officials laid the groundwork for what they call a reset in relations with Washington soon after Trump's election, ultimately forging a close relationship with Jared Kushner, the president's son-in-law and a senior White House advisor.
Meeting reporters on Thursday, Jubeir said Trump's trip to "the birthplace of Islam" shows his commitment to mending ties with Saudi Arabia and other Persian Gulf nations, which will gather for a summit with Trump on Sunday.
Jubeir said Arab leaders want to work with Trump on fighting extremism, blocking financing for terrorist groups, and countering Iranian-backed proxies or allies in conflicts in Yemen, Syria, Iraq and Afghanistan.
"We see them supply weapons to the Houthis including ballistic missiles that are fired at our cities," Jubeir said. "We see them doubling down in Syria. We see their heavy involvement in Iraq. We see them supporting terrorism. We see them now having contact with the Taliban. We see them trying to undermine countries throughout the region."
"The Trump administration is very cognizant of the dangers Iran represent to the region," he said, and will work "to contain Iran."
Jubeir said the kingdom has arrested several thousand people as members of Islamic State, and said he hopes for greater U.S. cooperation on counter-terrorism issues. Trump will visit a new Global Center for Combating Extremest Ideology in Riyadh during his visit.
Iran holds its presidential elections on Friday. Polls suggest President
In Washington, Sen.
"The Saudis are our friends," he said. "But they are also funding a version of Islam that ends up becoming the building blocks for the extremist groups that we're fighting."
Khaled Maeena, the Jeddah-based former editor of the Arab News and Saudi Gazette, said Arab leaders should hold Trump accountable for his harsh anti-Muslim rhetoric and his attempts to impose a travel ban on select Muslim-majority countries.
"Trump's election rhetoric really frightened a lot of people, even moderate Muslims like me," Maeena said.
He noted that Saudi Arabia severely restricts freedom of expression and religion, and do not allow the construction of Christian churches.
"In the Middle East there are so many minorities like Christians and as a Muslim I am appalled at what is happening to them," he said. "Trump talks about that, but only when he talks to evangelists at Liberty University, and even that he didn't do well."
Times staff writer W.J. Hennigan contributed from Washington and correspondent Josh Mitnick contributed from Tel Aviv
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