Special operators to Yemen; Crowdsourcing the next drone engine; Tesla’s military future; McCain v. Dempsey; And a bit more.

Houthi rebels launched their second cross-border attack in less than a week on Saudi Arabia’s southwestern Najran province on Tuesday—and Riyadh responded with more than 30 airstrikes on the border provinces of Saada and Hajja, according to Reuters this morning. For the first time, the Houthis fired mortars and rockets on Saudi civilian structures yesterday, killing at least three and capturing five soldiers, AP reports. The attack raises the possibility that Riyadh will need a large ground force in place sooner than later if it wants to consolidate any gains from more than a month of airstrikes on Houthi positions.
Special operations troops from Sudan are part of the Saudi-led “reconnaissance mission” that landed in the southern city of Aden on Sunday, McClatchy’s Tom Hussain reports. The Sudanese troops are among the nearly 50 special operators trying to take control of the airport in Aden ahead of plans to arm tribes loyal the exiled President Abd-Rabbu Mansour Hadi, as well as selective talks on the way ahead in Yemen scheduled for May 17 in Saudi Arabia.

Libya’s Air Force just bombed Islamic State-affiliated positions in the eastern city of Derna, the same city Egypt bombed after militants beheaded nearly 21 Coptic Christians in February. Libya’s government is struggling to beat back multiple armed groups that have risen up since Col. Moammar Gadhafi’s death almost four years ago. More on that from Reuters.

Gen. Martin Dempsey may be on his way out as chairman of the Joint Chiefs, but his vision for limited U.S. military intervention abroad looks almost identical to the advice given by his presumed successor, Marine Gen. Joseph Dunford, whom Obama nominated on Tuesday. Veteran Wall Street Journal national security reporters Julian Barnes and Adam Entous explore. A bit more on Dunford and Dempsey both below.

From Defense One

The State Department cleared the $3 billion sale of 17 Ospreys to Japan, missiles for Indonesia and Malaysia, a $21 million Blackhawk to Jordan, and almost $400 million in weapons for Iraq, Global Business Reporter Marcus Weisgerber reports.

The Air Force yesterday announced its largest-ever prize to a U.S. citizen ($2 million) who can build its next successful drone engine. Technology Editor Patrick Tucker lays out the requirements from Atlanta, where he’s covering the Association for Unmanned Vehicle Systems International, or AUVSI, conference.

Can Tesla change the military next? Founder Elon Musk’s new Powerwall battery could one day revolutionize the costs and operations of America’s forward bases abroador right here at home. Patrick Tucker explains the steps needed before that can become a reality.

McCain’s parting shot for Dempsey: “That’s why the world is on fire.” Sen. John McCain, R-Ariz., is pleased as peaches to see a new general show Dempsey the door, but doubts Obama will listen to the advice of the next Joint Chiefs chairman, Gen. Dunford. It all seems to boil down to the same issue: military intervention. Politics editor Molly O’Toole caught up with McCain to get his thoughts about the history of bad blood between the Senate Armed Services chairman and the Joint Chiefs chairman.

Iran is on the clock in the Senate, where Sens. Marco Rubio, R-Fla., and Tom Cotton, R-Ark., could derail a bill with hardline “poison pill” amendments—putting Mitch McConnell in a tight spot on a global issue, National Journal’s Lauren Fox and Alex Rogers explain.

A single battle in northern Afghanistan more than 13 years ago foreshadowed the contradictions and shifting allegiances that have characterized the struggle for Kabul’s future, Global Post co-founder Charlie Sennott writes from Mazar-i-Sharif.

No-fly zones can be an incredibly effective tool in contemporary warfare, but enforcing them comes at enormous risk and cost, writes Air Force colonel and military fellow at the Council on Foreign Relations Clint Hinote, in this handy explainer.

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An interconnected missile defense network across the Middle East is not a new idea, but it’s finally rising to the top of the agenda for next week’s meeting at Camp David between President Obama and the six nations of the Gulf Cooperation Council. U.S. officials are reviving a plan from former Defense Secretary Chuck Hagel that would build up, then link the missile defense systems of America’s Gulf allies to align against a possible threat from Tehran, according to Reuters this morning.
Mike Huckabee just backed Barack Obama on Iran, basically. “Hell will freeze over before [the ayatollahs of Iran] get a nuclear weapon,” Republican Mike Huckabee said yesterday while declaring his run for the White House. It was a line in a speech trying to out-tough guy the president on many issues, but in fact just repeats Obama’s own stance. Obama repeatedly has said he would not let Iran obtain nuclear weapon, via “all options.” Newsweek’s James Lindsay rolls up all the latest need-to-knows about Huckabee and his impassioned announcement yesterday from his Arkansas hometown of Hope.
Speaking of bad news for Iran, their militias operating in Iraq are hurting Tehran’s long-term interests with their “take no prisoners” approach to fighting ISIS in Tikrit, warns former CIA counterterrorism analyst Aki Peritz, in Slate.

The U.S. wants Iraq to remain a unified state, Obama and VP Joe Biden assured Kurdistan’s President Masoud Barzani, according to the AP. Barzani speaks at the Atlantic Council in Washington, D.C., at 10 a.m. today. You can livestream that one here.
The State Department just put multi-million dollar bounties on four ISIS leaders yesterday, though none of them topped the $10 million promised for the capture of ISIS leader Abu Bakr al-Baghdadi. AFP has more.

Meanwhile in Syria, President Bashar al-Assad said this morning he’s surging troops to northwestern Idlib province where his army has suffered significant setbacks from rebels in recent weeks, including the seizure of a Syrian army base.
And it keeps getting messier—a newly-formed coalition of rebels aligned with the Nusra Front in Syria is now being targeted by Hezbollah, the BBC says this morning. This follows reports that the Nusra-aligned fighters killed a Hezbollah commander in fighting along the Lebanese border with Syria on Tuesday. That via Lebanon’s The Daily Star.
Will a new energy project between Turkey and Russia both degrade Ankara’s reluctant role in the ISIS fight and undermine their effectiveness in NATO? The Center for American Progress’ Alan Makovsky investigates the U.S. foreign policy implications here.

Nearly 250 German police conducted raids across the country this morning arresting four suspects now being held on terrorism charges for trying to attack mosques, AP reports.
Remember when Germany was outraged U.S. intelligence agents had kept tabs on Chancellor Angela Merkel’s phone? This just in: everybody’s doing it. Germany’s own intelligence service, the B.N.D., is now in a bit of hot water over its own foreign spying across Europe, The New York Times Alison Smale reports from Berlin.
And in France, authorities can now tap phones and emails without court permission in a move that echoes the U.S.A. Patriot Act here in the states. The Guardian’s Angelique Chrisafis has more from Paris.

Today, the Air Force will award an airman the rare Air Force Cross while two others will receive Silver Stars for valor during a firefight in late September 2014 in Afghanistan’s Helmand province. The Washington Post’s Dan Lamothe has their stories.

Gen. Dunford’s legacy as the Afghanistan war commander in 2013 gives more than a few hints as to how he would likely lead the Joint Chiefs, WaPo’s Missy Ryan and Greg Jaffe write.
See also: US News’ Paul Shinkman provides one of the more well rounded profiles of Dunford over here.
And the Military Officers Association of America unsurprisingly threw their enthusiastic support behind Obama’s picks for the top posts at the Joint Chiefs. Read their statement encouraging a swift confirmation from the Senate right here.

Finally! The Army’s new Operational Camouflage uniforms hit shelves beginning July 1, an Army official told Kyle Janner of Army Times yesterday. Supply points, however, won’t begin issuing them to new recruits until January 2016. And the old uniforms—the urban digicamo Army Combat Uniforms, or ACUs—won’t be completely phased out until October 2018. Which means you’re apt to notice a hodge-podge of ACUs, Multicam and the new style on bases for the next three years. Consider the NCO corps warned.