Assad confronted; now what?; Trump-Xi, Day 2; After sarin, an information war; Top 5 underwater drones; and just a bit more...

Assad confronted; now what? The U.S. military carried out “the first direct U.S. assault on the government of Bashar al-Assad in six years of civil war” with some 50-plus volleys of Tomahawk Land Attack Cruise missiles targeting aircraft, hangars, fuel and ammunition stores, air defenses, and radars at Syria’s Shayrat Air Base, the facility from which Syrian government forces took off to drop chemical weapons two days ago, Defense One’s Marcus Weisgerber and Caroline Houck reported Thursday evening.

The justification: "The U.S. military saw the aircraft on a radar and watched them drop the bombs," U.S. officials told NBC News. "The radar soon picked up the flashes and booms in the rebel-held area of Syria."

Take a closer look: The Pentagon says these documents detail the flight path of the Syrian warplanes that carried out chemical weapons attack on Tuesday, Weisgerber reported from the building late Thursday.

Battle damage assessment: “About 20 Syrian aircraft destroyed in U.S. Navy Tomahawk missile strike at Assad's Shayrat airbase in Syria, U.S. officials say,” according to Fox News’ Lucas Tomlinson.

Russian television, meanwhile, “showed craters and rubble at the site of the airbase and said nine aircraft had been destroyed,” Reuters reports.

And purported photos of the damage are on offer from (h/t @peterwsinger, who adds, “BDA is changed in social media age”).

Reuters adds that the cruise strikes “killed six people and caused extensive damage” at the airbase. The Syrian army also described the cruise strikes as a “blatant act of aggression,” which puts the U.S. in league with al-Qaeda and ISIS.  

Other words used by Syrian officials to describe the attack: “short-sighted," “reckless” and “irresponsible,” USA Today reports.

The Kremlin’s spox, Dmitri Peskov, called the strikes an "aggression against a sovereign state in violation of the norms of international law and on a made-up up pretext,” al-Jazeera reports. “Washington's step will inflict major damage on US-Russia ties," Peskov predicted.

Moscow Times reports: “early Friday morning, the Russian Foreign Ministry announced the suspension of an airspace safety agreement with the U.S. and its allies.”

Russia’s military also took a far less optimistic view of the strikes’ effectiveness—claiming fewer than half of the missiles hit their intended target (an echo of the allegations levied against Russia during their cruise missile strikes of October 2015), according to USA Today: “Russian Defense Ministry spokesman Maj. Gen. Igor Konashenkov said six Syrian jets were destroyed but the air base's runway was intact. He said ‘the combat efficiency of the U.S. strike was very low’ and that 23 of the 59 missiles fired by the U.S. reached the base.”

Worth noting: The U.S. reportedly informed Russia in advance of the strikes. Also reportedly given advance notice: the Brits.

A big fan of the strikes: Turkey, Reuters reports.

So, what next? Negotiate regime change, Sen. Marco Rubio, R-Fla., says. "We need to now move forward through a combination of diplomacy and, quite frankly, the support of groups on ground, particularly non-jihadist Sunni groups, to create alternatives to the Assad regime,” Rubio told NBC’s “Today” show this morning. Video, here.

What Russia or Syria decided to do next: Strike the same town where the chemical attack allegedly occurred with another airstrike—this one apparently absent of chemical weapons, Reuters reports. The strike hit the northern edge of Khan Sheikhoun, “causing damage but no known casualties.”

Reminder: "At their closest point, [Syrian Democratic Forces and their U.S. special forces counterparts] are just eight kilometres from Raqqa city." More on that from the Middle East Eye, here.

Taking a step back for a moment: Here’s short recap of Thursday’s higher-profile events, via Gregory Korte of USA Today: House Intelligence Committee Chairman Rep. Devin Nunes, R-Calif., stepped down from the probe into Russian interference in the U.S. 2016 election; the U.S. Senate went “nuclear” and changed its rules to allow for the approval of Trump’s Supreme Court nominee, Neil Gorsuch; Trump met with Chinese President Xi Jinping at his Mar-a-lago resort; and, of course, the U.S. Navy launched airstrikes against Syria.

From Defense One

US Hits Syrian Airbase With Scores of Cruise Missiles // Marcus Weisgerber: A retaliation for the Assad regime's April 4 use of chemical weapons, the strike deepens the U.S. involvement in Syria's civil war.

The Sarin Gas Attack In Syria Ignited an Information Battle // Patrick Tucker: Victims quickly took to social media to distribute evidence of the use of chemical weapons.

WATCH: These are the cruise missile strikes President Trump just ordered in Syria // Defense One Staff: U.S. Navy warships have launched more than 50 cruise missiles at a Syrian airbase, marking a new escalation in the United States’ involvement in the country’s civil war.

The Fight Against the Islamic State Just Got Harder // Andrew Exum: Initial thoughts on the Trump administration’s new front in the Syrian war.

As Trump Meets China, US Worries About Beijing's Supercomputers and Industrial Espionage // Patrick Tucker: Network breaches? NSA research director says we ain't seen nothing yet.

The Global Business Brief: April 6 // Marcus Weisgerber: The new space race; L3 buys underwater drone firm; Satellite export deals stalled; Space socks; and more.

The Five Coolest Drones from America's Biggest Naval Arms Show // Patrick Tucker: New drones above and beneath the waves will change the way navies sail and fight in contested waters.

The US Was Already Fighting in Syria // Krishnadev Calamur: It has targeted ISIS and other terrorist groups, not the Assad regime—though that might change soon.

With Bannon Out, Here's Trump's New National Security Council // Heather Landy: The principals committee of the US National Security Council (NSC) suddenly looks a bit different than it did during president Donald Trump’s first month in office.

Veterans Calling VA's Crisis Line Can Finally Get Through. Here's Why. // Frank Konkel: A team of techies and customer-service professionals starting tackling the problem in 2015.

Welcome to this Friday edition of The D Brief by Ben Watson, Bradley Peniston, and Marcus Weisgerber. #OTD1917: the U.S. was one day into World War I. Got a message for us? Let us know by clicking this link to email:

It’s Day 2 of the Trump-Xi meeting. The Washington Post has a good rundown of what might happen and what’s at stake. Of note: the Trump administration is reportedly readying a plan to reduce imports of cheap Chinese steel, while the Chinese president might have brought “a package of pledges designed to give the U.S. president some 'tweetable' promises to present as victories.”

Xi definitely brought lots of seasoned America-watchers and diplomats, while Trump….less so. “The president’s skeletal team will be going up against a vastly more experienced Chinese corps of experts,” writes Politico’s Josh Meyer.

What won’t happen: “No joint news conference today either by Presidents Trump and Xi, who like most Chinese leaders, prefers not to be subjected to questions,” tweets CBS’ Mark Knoller.

Meanwhile, back in Asia: Philippines president Duterte orders his military to occupy some Philippine-claimed islands in the South China Sea, a measure intended to dispel Chinese attempts to exert influence. CNN, here.  

And the South Korean press is miffed at U.S. military press releases that said North Korea’s April 4 missile test (remember that?) fell in the “Sea of Japan,” which Koreans call the East Sea.

ICYMI: An Afghanistan police commander says Russians visited “Taliban training centers” in Waziristan, Pakistan, along with their Pakistani military counterparts, Afghanistan’s Tolo News reported Wednesday. A parliamentarian from Paktika province echoed that via second-hand reports, cautioning, “there is no information on whether the delegation promised help the Taliban or give them weapons.” More here.

SecState Tillerson heads to Moscow next week to discuss Ukraine, counterterrorism and bilateral relations with Russian officials, the State Department announced this week. Presumably, Syria will take a larger importance now, too.  

The King of Jordan has some advice for President Trump: Compromise with Russia on Crimea to get its help in Syria, he advised in an interview with the Washington Post: “Q. Do you want to see the U.S. engage with Russia over Syria?

A. I’ll tell you why that works: From the Russian point of view, they play what I describe as a three-dimensional chess game. To them, Crimea is important, Syria is important, Ukraine, and we see them in Libya. The Americans and Europeans must deal with the Russians on all these issues simultaneously.

Q. Once you understand these issues together, what do you do?

A. Then you horse-trade. For the Russians I think the most important thing is Crimea. If you come to an understanding on Crimea, I think you will see much more flexibility on Syria, and I think Ukraine then becomes the least problematic.” More here.

Russia is set to show off the world’s biggest nuclear sub in the Baltic Sea some time in late July, The Barents Observer reported this week. “TK-208 (Dmitry Donskoy) is the only remaining Typhoon-class submarine in operation. The 172 meter long giant was originally built to assure the Soviet Union’s ability to respond to a nuclear attack with a powerful retaliation. Carrying 20 missiles and up to 200 nuclear warheads, the sub could stay hidden under the Arctic ice cap and assure a second-strike against the attacker...the heavy missile submarine will sail out of the White Sea, across the Barents Sea on a voyage that continues along the coast of Norway, into the North Sea and Skagerak outside Denmark, and further across the Baltic Sea between Poland, Sweden and the Baltic States, before heading in to the Gulf of Finland towards St. Petersburg” for a parade on July 30. More here.

The U.S. Navy recently sent SecDef Mattis an “accelerated shipbuilding plan,” Inside Defense reported (paywalled) Thursday. The bill: an additional $61.8 billion over the Future Years Defense Program for 23 ships.

A win in Trump’s book: Kuwait will spend nearly $320 million to expand the Al Mubarak Airbase in Kuwait, the Defense Security Cooperation Agency announced Thursday. Details, here.

100 years ago yesterday America entered World War I. Scroll through “a collection of relatively-unseen images from a century ago, focusing on American war involvement, some on the home front, some overseas, and some images of their allies and enemies as well,” from The Atlantic’s Photo Editor Alan Taylor, here.  

Extended hours: As Defense Department officials (and reporters) worked late Thursday, there was a new late-night food option at the Pentagon: Subway. They eatery in the main food court is now open 24 hours, Convenient when you're staying late to monitor Tomahawk strike against Syria. Previously the only eatery in "The Building" open 24 hours was Dominic’s of New York, in the basement near the National Military Command Center. (Here’s a photo from CNN’s Barbara Starr.)

Lastly this week—satire alert: “Alien World To Help Out Syria Since This One Refuses To.” It’s an article from the humor site, The Onion, and it’s almost hard to believe it was originally written in 2012, less than a year after Syria’s armed uprising began. "We have monitored the ongoing violence in the region of your world known as Syria, and we find ourselves as disgusted by your reluctance to stop it as we are horrified by the deaths themselves," The Onion quoted a fictional alien they named Thuu'l. The article goes on a bit longer than the joke perhaps ought to; but you can read it for yourself in full, here.

As Abe Lincoln once said, “I laugh because I must not cry, that is all, that is all.” See you next week, everyone.