WASHINGTON — The US Senate voted overwhelmingly on Wednesday to overturn President Barack Obama's veto of legislation that would let relatives of the victims of the Sept. 11 attacks sue Saudi Arabia. 

The bill tees up the "Justice Against the Sponsors of Terrorism Act" to become law despite warnings from Obama and top Pentagon officials that it would put troops at risk and threaten a key strategic relationship in the Middle East.

The House voted 348-77 against the veto, just hours after the Senate voted 97-1. Senate Minority Leader Harry Reid, D-Nev., cast the upper chamber's lone "no" vote. The veto override is a first for Obama in nearly two terms in office.

The White House and several senators warned the bill could open a legal Pandora's Box, subjecting the US to legal action from people in other countries over injuries and deaths caused by military actions. That's because the legislation would tinker with the 1976 Foreign Sovereign Immunities Act, which supports the doctrine that the courts of one country do not sit in judgment of another government or actions within its borders.

"The president has strong views about this legislation and the impact that it would have not just on the US relationship with Saudi Arabia but with countries around the world," White House spokesman Josh Earnest said a day ahead of the vote. "It would increase the risk that is facing our service members and our diplomats and our intelligence professionals."

Joint Chiefs Chairman Gen. Joseph Dunford, in a recent letter to House Armed Services Chairman Mac Thornberry, R-Texas, said US troops, "especially those supporting counterterrorism operations," could be roped into litigation in a foreign court if they're alleged to have violated that country's law.

If a service member was sued in a foreign court, that court could decide whether information considered classified or sensitive by the US government is required as part of the litigation, Dunford told Thornberry. The service member would be forced to choose between disclosure and a negative ruling by that court.

"Finally, regardless of the specific legislation being considered, any legislation that affects the long-standing principles of sovereignty should carefully consider any risks to the close security cooperation relationships between the United States and our allies and partners," Dunford said in the letter.

On Wednesday, Thornberry made a floor speech warning of the "unintended consequences" of eroding sovereign immunity, which he called "one of the key protections that the military, diplomats, intelligence community of the United States has around the world."

"I understand totally the sympathies for the victims as well as the desires people have to override this veto, but we should also keep in mind the longer term consequences for our military who serve our nation all around the world," Thornberry said.

Several senators, even as they voted for the bill, said such concerns were driving them to follow up with a fix that narrows the bill; among them, Senate Foreign Relations Committee Chairman Bob Corker, R-Tenn., and Senate Armed Services Committee member Lindsey Graham, R-S.C., who said there are at least 20 senators who want the same.

Senate Armed Services ranking member Jack Reed, D-R.I., said a solution "absolutely" can and should get done in the post-election lame duck session in November.

"It's a possibility there might be some language that would help reduce concerns about a reciprocal response about American personnel," Reed said.

Graham warned the legislation, as it stands, guarantees US service members and diplomats would be "more exposed" and it would "rupture" the US-Saudi relationship.

"I see the relationship worth preserving, I see the legal needs of the 9/11 families to be real," Graham said. He also warned colleagues seeking the bill: "If you want to go forward in the Mideast without Saudi Arabia as an ally, then be careful what you wish for."

Though the US-Saudi alliance survived the oil embargo in 1973 and the Sept. 11 attacks, in which 15 of the 19 passenger-jet hijackers were Saudi citizens, the relationship is widely seen to be hitting a rough patch over the US-Iran nuclear deal.

Earlier this month, citing the humanitarian crisis and civilian casualties stemming from the Saudi campaign in Yemen, lawmakers drove a failed attempt in the Senate to block a $1.15 billion US arms sale to Saudi Arabia. US logistics and intelligence support has not proved enough leverage to get the Saudi government to show restraint, lawmakers say.

Still, security cooperation remains a pillar of the relationship, as the Obama administration has offered Saudi Arabia more than $100 billion in arms. Wednesday's veto override, while unwelcome in Riyadh, is unlikely to significantly tarnish its longstanding affinity toward the US defense industry, according to one analyst.

Fahad Nazer, an analyst at intelligence consultancy JTG and a former political analyst at the Saudi Embassy in Washington, said he would be surprised if the defense and diplomatic relationships suffered substantially, as they have benefited both countries.

"The fundamentals of the relationship are strong and I expect them to continue to be strong," Nazer said. "Arms sales and trade is the core of the relationship, and the US is committed to helping Saudi Arabia maintain its national security."

Sen. Chris Coons, D-Del., who served as the Senate's representative to the United Nations General Assembly last week, said Saudi Foreign Minister Adel al-Jubeir expressed to him "grave concerns about the potential negative impact that this vote may have on our strategic relationship."

"It is my hope that moving forward we can narrow the impact or consequences," said Coons, a member of the Senate Foreign Relations Committee. "The challenge we face is at the same respect Americans' right to a day in court and sustain and strengthen a critical alliance."

Saudi Arabia's longstanding support for hard-line Wahhabism, a source of concern for US lawmakers, "may be being reconsidered, or may be changing in some ways," Coons said.

The House Foreign Affairs Committee's top Democrat, Rep. Elliot Engel, of New York, voted for the override because he could not tell constituents who lost loved ones that they have no right to sue. Still, he hoped the US-Saudi relationship would not take a hit, in spite of differences between the two nations.

Engel, a staunch Israel supporter, touted the alignment of Washington, Riyadh and Tel Aviv's common strategic interests, alluding to Iran as a common security concern.

"This is a thing that I needed to vote for," Engel said of the legislation. "When we talk about the situation in the Middle East and Sunni Arabs, many of them have the same view as the US view on the Middle East, and in fact, many have the same view as Israel. The Sunni Arab countries are important allies."

Email:  jgould@defensenews.com

Twitter: @ReporterJoe

Joe Gould was the senior Pentagon reporter for Defense News, covering the intersection of national security policy, politics and the defense industry. He had previously served as Congress reporter.

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