Big bombing in Baghdad; Major weapons costs going down; Top US spy talks Mideast; Sarajevo’s lessons for Syria; And a bit more.

A massive car bomb killed more than 50 and wounded nearly 80 others in Baghdad’s Shi’ite Muslim district of Sadr City this morning. The Islamic State group was quick to claim credit for the attack, saying it dispatched a suicide bomber who drove the pickup truck packed with explosives that detonated “at rush hour near a beauty salon in a bustling market. Many of the victims were women including several brides who appeared to be getting ready for their weddings…The bodies of two men said to be grooms were found in an adjacent barber shop. Wigs, shoes and children's toys were scattered on the ground outside,” Reuters reports from the capital.

The numbing numbers: violence killed at least 741 Iraqis in April, the AP adds. “The U.N. mission to Iraq put the number of civilians killed at 410, while the rest it said were members of the security forces…In March, at least 1,119 people were killed and 1,561 wounded in the ongoing violence.”

On the front lines near Mosul, “suspicion and enmity” cloud Baghdad’s scotch-tape approach to keeping disparate factions like the Peshmerga and the Iraqi army united as ISIS gradually loses more turf, The Guardian’s Martin Chulov reports from Mahkmour.

“We don’t see them during the day,” said one Peshmerga soldier of ISIS fighters in the area. “They move around at night: they have dug tunnels, and they have laid bombs. All around us were bombs when we came into this village. It will be like this all the way to Mosul. Our friends [in the Iraqi army] can’t do this by themselves, and they know that.” More here.

Russia’s vision of a political solution in Syria is probably not gonna work, U.S. State Secretary John Kerry told CNN Tuesday about the ceasefire monitoring deal Washington has hammered out with Moscow—the only two nations the UN’s Syrian envoy said could bring an end to fighting since the UN itself clearly cannot.

“Are there still problems to work out? Yes,” Kerry said before launching into a quick who’s-who summary of the fighting. “There’s a five-year war, and it's really more than one war. You have Kurds versus Kurds, you have Kurds versus Turkey, you have Saudi Arabia and Iran, you have Sunni and Shiite, you have people against Daesh [ISIS] and people against Assad. I mean, this is a very complicated battlefield,” he said.

Any agreement reached on Syria is, ultimately, nothing more than “words on a paper,” he continued. “The key is going to be enforcement. We’re looking at other methods of enforcement beyond that. But we’re not there yet, but we're building what I hope will be a stronger structure.”

There are a few lessons for Syria from “the longest siege of a major city in modern warfare,” the siege of Sarajevo in the mid-90s, write Maj. Mike Jackson and Lionel Beehner—the deputy director and director of research of the Modern War Institute at the U.S. Military Academy at West Point—in the pages of the Washington Post. “First, in Sarajevo, neither side had an effective approach to fighting in a major urban area, falling into static positions reminiscent of World War I trench warfare from which neither could break the stalemate. We should expect the same in Aleppo: If the forces aligned with the Syrian regime want a quick and decisive military victory, they probably cannot achieve it, even with Russian air support.”

Another lesson: “cease-fires can be effective in ending a siege but can also be counterproductive... Even when handled well, cease-fires can harden or radicalize the existing positions. Arguably, similar dynamics are present in Aleppo.”

The bottom line: The siege of Aleppo could last for years. “If history teaches us anything, it’s that we cannot expect a lasting peace without an overwhelming third party intervention to force the belligerents to the table. The question is whether that third party will be Russia, NATO-backed forces or Russia and NATO-backed forces working together in some marriage of convenience.” Read the rest here.

Here’s what the ceasefire looks like south of Damascus this morning.

After nearly four years of sorties and strafing runs from nearly-junked trainer jets, what’s really left of the Syrian air force? “Currently, what is left of the SyAAF is concentrated at five major air bases, each of which is a home for units usually operating fewer than a dozen of airframes,” writes Tom Cooper over at War Is Boring. He digs into the losses, downed jets, increasingly reckless pilots and more, here.

Newsflash: the U.S. can’t fix the Middle East, Director of National Intelligence James Clapper told WaPo’s David Ignatius. “They’ve lost a lot of territory,” Clapper said in his Monday sit-down with Ignatius. “We’re killing a lot of their fighters. We will retake Mosul, but it will take a long time and be very messy. I don’t see that happening in this administration.”

And that’s the good news, since even after the group is presumably wiped out in Iraq and Syria, Clapper said, “We’ll be in a perpetual state of suppression for a long time.”

Clapper’s answer: “I don’t have an answer…The U.S. can’t fix it. The fundamental issues they have — the large population bulge of disaffected young males, ungoverned spaces, economic challenges and the availability of weapons — won’t go away for a long time… the expectation is that we can find the silver needle, and we’ll create ‘the city on a hill.’” That’s not realistic, Clapper said.

And yet: “I don’t think the U.S. can just leave town. Things happen around the world when U.S. leadership is absent. We have to be present — to facilitate, broker and sometimes provide the force.” Read the rest here.

From Defense One

GPS upgrades are late and over budget. Here’s why we should stay the course. Essentially, there’s no better alternative to the GPS III and OCX programs, which thankfully appear to be on track at last. Former House intelligence chair Silvestre Reyes makes the argument, here.

Why is the U.S. military short-staffing its sickest children? The military health-care system serves 2 million children with just a handful of full-time pediatric social workers. In the civilian world, this kind of staffing is “unimaginable.” From The Atlantic, here.

Trump may be the U.S. military’s least-liked GOP presidential candidate in over a decade. Mitt Romney, John McCain, and George W. Bush all polled higher, according to Military Times surveys. That via Quartz, here.

Welcome to the Wednesday edition of The D Brief, by Ben Watson and Bradley Peniston. On this day in 1846, President James Polk launched the Mexican-American War. Send your friends this link: And let us know your news:

The Pentagon says it’s saving money on weapons. The heads of the Pentagon’s big arms projects are finding ways to cut costs. Between 2009 and 2014, there has been a “significant positive shift” in the amount of money cut from programs’ original cost estimates, according to briefing slides presented by Frank Kendall, the Defense Department’s undersecretary for acquisition, at an event yesterday at the Center for Strategic and International Studies. Said another way, the programs spending less cash than planned. Kendall credits the “should cost” initiative, part of the Better Buying Power acquisition reforms, which requires project managers to look for ways to save money and set targets for doing so. “This is a major cultural change that seems to be taking hold,” Kendall wrote last year in his annual report card for the acquisition system.

ICYMI: So if cost growth is coming under control, what’s the next big challenge for Pentagon buyers? Figuring out how to buy weapons that can be quickly and easily modified. That, from CSIS’ Andrew Hunter, here.

The U.S. is turning on that Aegis system in Romania tomorrow despite Russia’s wishes, Reuters reports. And it’s starting construction on a second site in Poland set to go online in 2018. U.S. officials call Russia’s worry a case of “strategic paranoia,” and you can find out why here.

Former SecDef Chuck Hagel says NATO is playing with fire as it mulls sending four battalions of troops to Russia’s doorstep, he told a crowd at the Atlantic Council on Tuesday. “If I were secretary of defense today, I’d be careful with this because, I’m not opposed to it, but we can find ourselves very quickly in another Cold War buildup here, that really makes no sense for either side,” he said. “I’m not sure there's some real strategic thinking here.” The Hill has more here.

The Navy has ordered Lockheed Martin to fix a few major things on its littoral combat ships. The orders were given last year in the wake of problems with the ships’ propulsion systems, among other issues. Reports Bloomberg: “The Defense Contract Management Agency found Lockheed has ‘systemic quality deficiencies’ at the Marinette Marine Yard in Wisconsin, where it builds the ships, agency spokesman Mark Woodbury said in an e-mail.” Read on, here.

The likely collision of James Baker and Donald Trump. The former secretary of state and longtime Bush ally drops in on the Senate Foreign Relations Committee on Thursday to discuss America’s role in the world—a meeting that could bring Baker’s realist view with what Politico calls “Trumpism” as the GOP prepares for the months ahead. Catch the short preview of that visit to Capitol Hill, here.  

Lastly today: Watch those A-10s the U.S. sent to Korea as they take part in an “elephant walk” exercise, which tests a “squadron’s ability to launch large formations of aircraft at short notice,” writes The Aviationist. For the record: “‘Elephant Walks’ are particularly frequent in South Korea where local-based U.S. Air Force jets (often alongside Republic of Korea Air Force planes) frequently stage such ‘collective shows of force’ in response to North Korea’s aggressive posture and threats.”

This one happened two days ago “and involved more than 40 aircraft (looks like they are 43), including 15 A-10 Thunderbolt II aircraft with the 25th Fighter Squadron ‘Draggins’ and F-16 Fighting Falcon aircraft from the 51st Fighter Wing, Osan Air Base, South Korea, with some additional F-16 aircraft with the 179th Fighter Squadron ‘Bulldogs’ from the 148th Fighter Wing out of Duluth Air National Guard Base, Minnesota.” Catch them all, here.