US-Saudi relations get complicated; Death toll rises in Kabul; How to retake a booby-trapped city; DoD’s 5-year plan still exceeds spending cap; and a bit more.

The U.S.-Saudi relationship slides into focus today as President Obama visits Riyadh to meet with King Salman ahead of a Thursday session of the Gulf Cooperation Council. Complicating that picture is the “long-delayed release of congressional documents that concluded Saudi officials in the United States might have played a role in the Sept. 11 terrorist attacks,” the New York Times reports.

But first: the list of Saudi grievances is not short, the Times writes: “The Obama administration’s deal with Iran to limit that country’s nuclear program has unnerved the kingdom. The president’s decision not to order airstrikes against the forces of President Bashar al-Assad of Syria in 2013 was viewed in the kingdom as hesitation in the face of an implacable foe. And the Saudis were angered by Mr. Obama’s comments in a recent article in The Atlantic in which he suggested that Persian Gulf countries were not pulling their weight in assuring the region’s security.”

Plus: “Conflicts in Syria and Yemen have raged on with little U.S. involvement, encouraging the use of proxy forces by Iran and its Gulf rivals. And a sharp reduction in U.S. foreign-oil consumption has added to disarray in energy markets,” the Wall Street Journal adds.

And now back to 9/11: “Questions about the possibility of Saudi involvement in the terrorist attacks almost 15 years ago have also given rise to a bill in Congress that would allow American citizens to sue the Saudi government,” NYTs writes. “The legislation has strong, bipartisan support; Saudi officials have threatened to sell off nearly $1 trillion in assets if the bill becomes law.”

Understatement of the trip: “[O]ur views and those of some of our partners in the region, and Saudi Arabia in particular, have not always been perfectly aligned,” Rob Malley, the president’s top Middle East adviser, told reporters last week. Still, White House officials are saying they believe “that the common cause of combating terrorism and regional instability would be enough to ensure a productive meeting with the king, as well as a positive summit meeting with other Persian Gulf leaders on Thursday.”

For what it’s worth: Obama meets with “French, British, Italian and German leaders in Hannover next week for discussions expected to touch on Syria, Libya, the Islamic State group and migration,” AP reports from Paris.

Elsewhere in Riyadh today: U.S. Defense Secretary Ash Carter meets with his GCC counterparts, which include Kuwait, Bahrain, Qatar, the UAE, Oman and Saudi Arabia.

Here’s some advice: Instead of the U.S. hawking “prestige weapons” worth billions to its Mideast allies, Washington should look to the UAE’s special operators or even Palestine’s security forces as a blueprint for future U.S.-Mideast relations, argue Ilan Goldenberg and Peter Kirechu of the Center for a New American Security, writing in Defense One.

Speaking of U.S. weapons to the Middle East: Here’s “how Saudi Arabia has killed 2,000 civilians in Yemen with U.S. weaponry,” David Rohde tweeted last night about a stinging Reuters investigation into the Saudi military’s prowess, or lack of same, in taking on an Iranian-backed insurrection to its south. “Instead of being the centrepiece of a more assertive Saudi regional strategy, the Yemen intervention has called into question Riyadh’s military influence, said one former senior Obama administration official. ‘There’s a long way to go. Efforts to create an effective pan-Arab military force have been disappointing.’” Read on, here.

Bonus chart: What do 45 years of U.S. arms deals to the Saudis look like? This.

Kabul’s death toll more than doubled from initial reports after the Taliban’s truck bomb attack at morning rush hour, Afghan officials said this morning. “It is with regret that I announce that 64 people were killed and 347 others wounded in yesterday’s Kabul attack,” ministry spokesman Sediq Sediqqi told reporters. “Most of them are civilians.” The ministry had earlier put the death toll at 30, Agence France-Presse reports.

Take a look at the “endless” fighting season in Afghanistan, courtesy of a report by the Soufan Group. Their BLUF: “As in Iraq, the U.S. will likely once again increase its military involvement in Afghanistan, with no near-term prospects for meaningful improvement.” More here.

Retaking a booby-trapped city, with U.S. help. Months after Iraqi troops flushed ISIS from Ramadi, the work of making the city safe is just beginning. And it’s getting a boost from a Tennessee-based company with a history of post-conflict bomb-removal in places like Laos and Bosnia, Defense One’s Global Business Editor Marcus Weisgerber reports. More from the ISIS fight below.

From Defense One

Join Defense Secretary Ash Carter and some of the brightest minds in military and consumer technology to discuss the future of innovation and national security at the first-ever Defense One Tech Summit on Friday, June 10, at the Newseum in Washington, D.C. Reserve your early seat, here.

The U.S. military wants a “privacy firewall” so it can use info gleaned from social-media to help during disaster response. A new tool to strip personal information from tweets and social media could help troops zero in on trouble spots, reports Tech Editor Patrick Tucker, here.

Three ways to judge the Pentagon’s tech-sector outreach. Hint: it’s not about how many zeroes are on the first checks. Avascent’s Christopher Meissner and August Cole lay out things to watch as Ash Carter’s pet initiative prepare to make its first outlays in August. Read, here.

Welcome to the Wednesday edition of The D Brief, by Ben Watson and Bradley Peniston. On this day in 1918, the Red Baron notched his 79th and 80th aerial victories, one day before his death. Shoot your friends this link: http://get.defenseone.com/d-brief/. And let us know your news: the-d-brief@defenseone.com.

What’s the Pentagon getting for $583 billion? In a new report, budget guru Todd Harrison of the Center for Strategic and International Studies offers his annual critique of Pentagon spending. Some highlights: The Defense Department civilian-to-military ratio (0.6 to 1) is the highest since World War II (and that doesn’t include contractors). Related: Civilians are only a small fraction (4.1 percent) of the headquarters staffs that Pentagon leaders want to cut. Also: About half of the military’s war budget ($30 billion) is being spent on base budget activities. Bottom line: Pentagon is still betting on the come — its five-year spending outlook is $233 billion above federal spending caps. Much more, here.

The Pentagon is cleared hot—a bit more so, anyway—in its air war against ISIS, USA Today’s Tom Vanden Brook writes from the CIVCAS front: “Six [anonymous] Defense Department officials… described a sliding scale of probable civilian casualties based on the value of the target and the location. For example, a strike with the potential to wound or kill several civilians would be permitted if it prevented ISIL fighters from causing greater harm. Before the change, there were some limited cases in which civilian casualties were allowed, the officials said. Now, however, there are several targeting areas in which the probability of 10 civilian casualties are permitted. Those areas shift depending on the time, location of the targets and the value of destroying them, the officials said.” Worth the click, here.

Dollars and cents: The amount the U.S. has spent fighting ISIS, from Aug. 8, 2014, through Mar. 15, 2016, is $6.8 billion. That comes to $11.5 million for each of the 586 days, The Hill’s Kristina Wong tweeted Tuesday.

Bombing democracy out of NW Syria—following up on reports of allegedly organic protests against al-Qaeda’s Syrian wing, Jabhab al-Nusra, in the northwestern city of Maarat al-Numan, the Washington Post reports Assad’s jets (or Russia’s, it’s not 100 percent clear) killed at least 37 people there at the town’s main market on Tuesday. “There were people who lost arms and legs,” a resident said. BBC this morning reports the death toll has risen to at least 44. More here.

Ceasefire sitrep: It’s been “buried” by the Assad regime’s air force, Anas al-Abda, the leader of the Syrian National Coalition, said this morning.

Revealing new bomber’s price tag would make us all less safe, Air Force insists. “There is a ‘strong correlation between the cost of an air vehicle and its total weight,’ Randall Walden, director of the Air Force’s secretive Rapid Capabilities Office, which is overseeing the B-21 program, wrote in a letter to Senator John McCain, chairman of Senate Armed Services Committee. ‘This correlation makes calculating aircraft range and payload decisively easier for our adversaries looking to develop countermeasures,’ Waldon wrote in the letter dated April 11 and obtained by Bloomberg News.” What else about the B-21 is classified? Its “size, required stealth, structure, number and type of engines, and onboard sensors,” Bloomberg’s Tony Capaccio reports.

Remember that story about the F-35 helmet that would snap light pilot’s necks? The problem may be behind us, Defense News reports. They tested three helmet variants on a 103-pound dummy and the dummy lived—or rather, if the dummy were a human, that fella would probably have survived the test. Read what difference six ounces reportedly makes for the future of American air power, here.  

Lastly today—see for yourself how China’s lone aircraft carrier, the Liaoning, stacks up against its naval peers from India, Japan and the U.S. in this deep-dive (with interactive 3D model) from the good folks at the Center for Strategic and International Studies.