Iran: we downed jet; SecDef contradicts Trump on strike justification; A 3rd targeted killing failed; US KIAs ID’d; And a bit more.

“The Islamic Republic of Iran deeply regrets this disastrous mistake,” Iranian President Hassan Rouhani announced Friday, following days of detailed reporting from the New York Times and Bellingcat, whose reporters scoured and aligned open source imagery and videos to show the tragic shootdown of Ukrainian Flight 752.

Spotted over the weekend in Iran: Large scenes of protest on the streets and outside universities in the cities of Isfahan and in Tehran, Reuters reports today, which is the third consecutive day of such protests, according to the Washington Post.

“Clerics, get lost!” shouted some of the protesters today, according to Reuters. And “Khamenei have shame. Leave the country," was another refrain in Tehran on Sunday, when “Iranian riot police used tear gas to disperse thousands of protesters in Tehran's Azadi Square,” CNN reports.

U.S. President Donald Trump tweeted his support for the protesters Sunday morning, writing, “To the leaders of Iran - DO NOT KILL YOUR PROTESTERS. Thousands have already been killed or imprisoned by you, and the World is watching. More importantly, the USA is watching. Turn your internet back on and let reporters roam free! Stop the killing of your great Iranian people!”

By the way: Trump authorized Soleimani's killing 7 months ago “if Iran's increased aggression resulted in the death of an American,” NBC News reports this morning, citing five current and former senior administration officials. “That decision explains why assassinating Soleimani was on the menu of options that the military presented to Trump two weeks ago for responding to an attack by Iranian proxies in Iraq, in which a U.S. contractor was killed and four U.S. service members were wounded, the officials said.”

That could present a problem, NBC writes, since the timing “could undermine the Trump administration's stated justification for ordering the U.S. drone strike that killed Soleimani in Baghdad on Jan. 3. Officials have said Soleimani, the leader of the Islamic Revolutionary Guard Corps' elite Quds Force, was planning imminent attacks on Americans and had to be stopped.”

But Defense Secretary Mark Esper said to CBS News’s Margaret Brennan that he didn't see any specific evidence that Iran had planned to attack four U.S. embassies, like Trump claimed as justification for the strike. 

Another thing we learned this weekend: The day Solemiani was killed, the U.S. launched another secret operation to kill a senior Iranian official in Yemen — but this one did not succeed, according to the Washington Post’s John Hudson, Missy Ryan and Josh Dawsey.

This, too, could present a problem for WH officials since the news “rais[es] questions about whether the mission was designed to cripple the leadership of the Islamic Revolutionary Guard Corps or solely to prevent an imminent attack on Americans as originally stated.” More here.

Meantime: U.S. threatens to hit Iraq in its wallet. Kicking U.S. forces out of Iraq will cost Baghdad access to its own "central bank account held at the Federal Reserve Bank of New York," the Wall Street Journal reported Saturday in "a move that could jolt Iraq’s already shaky economy."

What’s going on here: “Iraq, like other countries, maintains government accounts at the New York Fed as an important part of managing the country’s finances, including revenue from oil sales. Loss of access to the accounts could restrict Iraq’s use of that revenue,” the Journal writes, “creating a cash crunch.”

Said an adviser to Iraq’s prime minister: “If the U.S. does that, it will lose Iraq forever.” 

FWIW: Baghdad is mulling an S-400. Members of the Iraqi parliament said the country was considering buying a Russian air-defense system, according to the Wall Street Journal reporting Friday. In case you were curious, “An Iraqi move to buy the system could trigger U.S. sanctions under laws requiring measures against those who do business with Russia’s defense sector, though the White House would have to determine to what extent those sanctions would be imposed.” 

Two U.S. soldiers died on Saturday when their vehicle hit an IED in Afghanistan's southern Kandahar province. 

• Staff Sgt. Ian P. McLaughlin, 29, of Newport News, Virginia.
• Pfc. Miguel A. Villalon, 21, of Joliet, Illinois. 

Both soldiers were assigned to the 82nd Airborne Division’s 307th Brigade Engineer Battalion, 3rd Brigade Combat Team. The Washington Post’s Dan Lamothe reported “McLaughlin was a 29-year-old father of four.” Find images of both paratroopers, here.

From Defense One

Iran’s Smart Strategy // Tom Nichols, The Atlantic: The Iranians chose neither to fold nor to fight. It is not clear at this point who was more deterred by whom.

Trump Broke It. Now He Owns It. // David Frum, The Atlantic: The president withdrew from a flawed deal with Iran, but had no realistic alternative. With that choice comes responsibility for what ensued.

Building Post-INF Missiles Would Be a Waste, or Worse // Kingston Reif and Shannon Bugos: New U.S. intermediate-range ground-launched missiles would deliver more undesirable effects than tactical utility.

DARPA Aims to Develop a ‘Sea Train’ of Unmanned Warships // Brandi Vincent, Nextgov: The Pentagon’s research arm is looking for technologies for a new class of long-distance unmanned surface vessels.

Welcome to this Monday edition of The D Brief from Ben Watson and Bradley Peniston. If you’re not already subscribed, you can do that here. On this day in 1893, U.S. Marines landed in Hawaii. Four days later, they were directed to protect the militia that overthrew the Hawaiian queen.

A Russian destroyer nearly collided with a U.S. one in the north Arabian Sea on Thursday before sharply turning away at the last minute, Navy Cmdr. Joshua Frey, a spokesman for the U.S. Fifth Fleet in Bahrain, said in a statement on Friday — followed by a Twitter thread with videos illustrating the encounter. 
Said the Fifth Fleet: “While the Russian ship took [eventual] action, the initial delay in complying with international rules while it was making an aggressive approach increased the risk of collision. The U.S. Navy continues to remain vigilant and is trained to act in a professional manner.
The last similar encounter that’s known publicly happened last June in the Philippine Sea about 200 miles from Japan, the WSJ reported Friday. At the time, “a Russian destroyer came within about 100 feet of an American destroyer, the USS Chancellorsville… The Russian ship continued closing in directly on the American warship before the crew of the Chancellorsville made an emergency maneuver to avoid collision.”

On Friday evening, President Trump told Fox that Saudi Arabia had deposited $1 billion “in the bank” in exchange for American forces deploying to Saudi Arabia. (Was this it?) The president then said South Korea will be paying $500 million to the U.S. for defense against North Korea. 
Here’s what Trump said earlier in the day Friday about possibly pulling U.S. troops from Iraq: “I’m OK with it.” (h/t CNN’s Manu Raju)
Also on Friday: Republican Rep. Doug Collins of Georgia apologized for accusing Democrats of being “in love with terrorists,” the Wall Street Journal reported.

More than a dozen Saudi servicemen training here stateside will be expelled after a review that followed the deadly shooting last month in Pensacola, Fla. According to CNN, none of them are suspected of having helped the shooter when he killed three U.S. sailors, but “some are said to have connections to extremist movements, according to a person familiar with the situation.” 

Apropos of nothing: “The Washington National Cathedral blessed the official Bible for the new Space Force,” according to the Cathedral’s Twitter account on Sunday. The Cathedral’s Bible “will be used to swear in all commanders of America's newest military branch.” 
Related: In 2014, the Air Force — the service with arguably the most sway over the nascent Space Force — decided to make its new recruits say “so help me God” during their enlistment ceremonies, even rebuffing one would-be airman who refused. Later that year, the threat of a lawsuit led to a quick review of the U.S. Constitution’s Article 6, which led senior leaders to drop the phrase.  

Libya's renegade Gen. Khalifa Haftar declared a ceasefire this weekend, which at least temporarily ends his “nine-month campaign to seize the capital, Tripoli,” CNN reported on Sunday. 
Today, the two main sides in Libya’s conflict are meeting in Moscow, al-Jazeera reports. Those two sides’ leaders include Fayez al-Sarraj, “the chief of the internationally recognised Government of National Accord, and his rival, renegade commander Khalifa Haftar.” The two men are reportedly very close to making the ceasefire official — thanks to talks that both the leaders of Russia and Turkey are taking credit for. 
For Turkey's part today, Reuters reports from Ankara that President Recep "Erdogan said he will attend a summit in Berlin on Sunday to discuss developments in Libya, along with [Italian Prime Minister Giuseppe] Conte and Russian President Vladimir Putin."

And finally: Welcome back, Kori! Starting today, Kori Schake officially takes over as Director of Foreign and Defense Policy Studies at the American Enterprise Institute think tank in Washington. Schake comes to AEI from the International Institute for Strategic Studies in London, where she was IISS’s deputy director-general. Before that, she held positions in the U.S. State Department, the Department of Defense, and the National Security Council at the White House. 
Last June, she sat down for a conversation with Defense One’s Kevin Baron on the sidelines of the 2019 Shangri-La Defense dialogues in Singapore. You can also find what Schake has written in the op-ed pages of Defense One, here.