Before the start of business, Just Security provides a curated summary of up-to-the-minute developments at home and abroad. Here’s today’s news.

YEMEN 

Saudi-led air campaign resumes in Sana’a. Warplanes hit targets in Yemen’s capital on Sunday for the first time since the campaign against Shi’ite Houthi rebels was said to be refocusing toward a political, diplomatic solution. Combat was reportedly some of the most widespread since the start of the Saudi intervention last month, a marked escalation in fighting. [New York Times’ Saeed al-Batati and Kareem Fahim; Reuters’ Mohammed Mukhashaf and Mohammed Ghobari]

The threat of a U.S.-Iranian confrontation in the Gulf of Aden has abated, Pentagon officials said Friday, confirming that the nine-ship Iranian convoy had reversed course. [AP’s Robert Burns]

Yemen’s factions were close to reaching a power-sharing deal as Saudi-led airstrikes began a month ago, throwing off the negotiations, said Jamal Benomar, the UN special envoy to Yemen who spearheaded the negotiations until his resignation last week. [Wall Street Journal’s Joe Lauria and Margaret Coker]

Yemen’s foreign minister Riyadh Yaseen rejected a call for peace talks from ousted former president Ali Abdullah Saleh, saying there was “no place” for Saleh in any future talks. [Reuters] 

IRAQ and SYRIA

A coalition of Islamist rebel groups claim to have seized a Syrian army base in Idlib province early today, following a suicide attack by the Nusra Front inside the base. The capture, if confirmed, would be the latest in a string of losses by the Syrian army in the region. [Reuters]  The town of Jisr al-Shughour, also in Idlib, was captured on Saturday. The rebel victories are “overturning long-held assumptions about the durability of President Bashar al-Assad’s regime,” reports Liz Sly. [Washington Post]

Israel conducted an airstrike on its Syrian frontier on Sunday, targeting militants spotted carrying explosives in the Israeli-held Golan Heights. No figures were given for casualties from the strike. The Syrian Observatory for Human Rights said four Syrian soldiers were killed by a missile in Golan, but it was not clear what the source of that missile was. [AP’s Ian Deitch]  Israel has denied responsibility for a further strike attributed to it today. [Haaretz’s Jack Khoury et al]

Two Swedish citizens, held hostage by the Nusra Front in Syria for 17 months, were freed on Friday. A Palestinian intelligence official provided the first details of the release; the Palestinians became involved as mediators after Swedish authorities requested the help of Palestinian President Mahmoud Abbas in February. [AP’s Ian Deitch]

The TSA has issued a classified warning regarding a potential attack by the Islamic State over the weekend against a target on U.S. soil. The warning is “significant” in that it highlights the seriousness with which the intelligence community is considering potential ISIS attacks in the U.S., reports Jana Winter. [The Intercept]

U.S. DRONE PROGRAM  

President Obama approved a waiver granting the CIA greater flexibility in Pakistan to conduct its drone program, even as rules for drone strikes were strengthened in 2013, according to current and former officials. [Wall Street Journal’s Adam Entous]

The drone program has “unwavering support from Capitol Hill” and is unlikely to be substantially altered despite the president’s announcement last week, as the CIA program is deeply “embedded in American warfare,” report Mark Mazzetti and Matt Apuzzo. [New York Times]

Senate Armed Services Committee Chairman John McCain said the military should be responsible for the country’s drone program, not the CIA, in an appearance on CNN’s “State of the Union” yesterday.

“The absence of transparency … has been a defining feature of the Obama administration’s drone program,” and the “unprecedented” openness last week regarding the accidental killing of two Western hostages raises the question of when the president will “apologize for all the other innocent victims of drone strikes,” writes Ryan Devereaux. [The Intercept]

AFGHANISTAN 

The Pentagon cannot account for $1.3 billion in Afghan reconstruction aid given between 2004 and 2014, a figure amounting to 60% of all such spending under an emergency program. [McClatchy DC’s James Rosen]

An explosion inside a house in Afghanistan’s southern Zabul province killed five civilians last night; the bomb detonated during clashes between north Taliban insurgents and the police. [AP]

IRAN NUCLEAR DEAL

Secretary of State John Kerry will meet his Iranian counterpart Mohammad Javad Zarif today at a UN conference on the Nuclear Non-Proliferation Treaty; the two will aim to advance nuclear negotiations on the sidelines of the conference. [Reuters’ Louis Charbonneau]

Former President George W. Bush questioned the lifting of Iran sanctions and expressed concerns about the impending nuclear agreement with Tehran during an address on Saturday. [New York Times’ Jason Horowitz and Maggie Haberman]

A number of proposed Republican amendments to the Iran bill, which allows congressional review of any agreement reached with Iran, are threatening to weaken the bipartisan support for the measure, reports Jordain Carney. [The Hill]

Tehran “continues to expand its reach” and a nuclear accord will not lead it to “enter the international system as a responsible actor,” write former U.S. ambassador to Iraq James F. Jeffrey et al in a New York Times op-ed.

RUSSIA and UKRAINE

Ukraine called for support from allies, urging them to send weapons, as NATO accused Russia of an increased military presence along its Ukrainian frontier. [Bloomberg News’ Volodymyr Verbyany and Henry Meyer]

Ukraine’s efforts to better train and prepare its military are being undermined by “draft dodgers,” or prospective soldiers avoiding conscription. [Washington Post’s Karoun Demirjian]

GUANTANAMO BAY

Four former Guantanamo detainees continued their protest outside the U.S. embassy in Uruguay for a third day on Sunday, calling for housing and financial support from the U.S. [AP]

Carol Rosenberg reviews Mohamedou Ould Slahi’s Guantanamo Diary, the only memoir to be released while the author is still in detention. [Miami Herald]

OTHER DEVELOPMENTS

Potential change in U.S. hostage policy. The White House-ordered review on the subject is expected to conclude that families of hostages will be free to pay ransoms without fear of prosecution for aiding terrorists, according to senior officials. [ABC News’ Brian Ross and James Gordon Meek]

The NSA’s post-9/11 warrantless surveillance was less useful owing to the secrecy surrounding the program, according to a newly declassified document, which also indicates that the program made the most limited contribution to counter-terrorism efforts. [New York Times’ Charlie Savage]

Lawyers for Jeffrey Sterling have requested in their sentencing memorandum that the former CIA officer, convicted of leaking classified information, should “not receive a different form of justice” than former CIA director David Petraeus. [The Intercept’s Peter Maass]

“The anguish of moral injury” may be the “deepest wound” sustained in war; Nancy Sherman explains how this is separate from post-traumatic stress disorder and includes “falling short of the lofty ideals of military honor.” [Los Angeles Times]

The next UN Secretary General should be a woman, argue Gillian Sorensen and Jean Krasno in a Washington Post op-ed.

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