Today's D Brief: Russia launches new offensive; US to stop ASAT testing; Drama in the Solomons; Judge ditches mask mandate; And a bit more.

Russia has reportedly begun its offensive in eastern Ukraine. A new phase of Russian heavy shelling began late Monday and early Tuesday at locations near Kharkiv, Mykolaiv, and on Ukrainian military positions across the Luhansk and Donetsk oblasts, in the southeast. Alleged “large-scale assaults focused on Rubizhne, Popasna, and Marinka” began Monday as well, according to analysts at the Institute for the Study of War. 

This could be a grueling, grinding campaign of seemingly indiscriminate bombing, since Russian military doctrine has been known to lean heavily on artillery bombardment (or “the employment of indirect fires en masse,” as RAND Corporation’s Scott Boston and Dara Massicot described it in 2017) as a way to break through defensive lines. However, ISW warns, “the Russian military has few, if any, cohesive units not previously deployed to Ukraine to funnel into new operations.” 

Few expect it to be as clumsy and vulnerable as Russia’s opening gambit, when several invading armored elements raced to Kyiv, stretching well beyond supply lines, which the Ukrainians shredded with anti-tank weapons like Javelins from the U.S. and NLAWs from the U.K. The brutality of Russia’s new phase of operations could eclipse its first, especially coming off last week’s loss of the Black Sea flagship Moskva. But most observers expect Russia to adapt and absorb at least some lessons from the first six weeks of the invasion. 

Developing: Russia now has 76 battalion tactical groups inside Ukraine’s borders, which could be between 50,000 and 60,000 troops—with around 600 to 800 soldiers in each BTG; and they’re all spread across the south and east, a senior U.S. defense official told reporters Monday at the Pentagon. But it’s anyone’s guess how the morale is across those units since, as ISW notes, “Russian forces did not take the operational pause that was likely necessary to reconstitute and properly integrate damaged units withdrawn from northeastern Ukraine into operations in eastern Ukraine.” And the battle for Mariupol is ongoing; if concluded soon, it could free up as many as a dozen more BTGs for the eastern offensive. 

Russian air activity isn’t terribly revealing, the U.S. defense official said Monday. Moscow’s pilots have been consistently flying about 200 sorties daily for the last several days, and that’s “not totally all that different [from] what we've seen in the past.” 

But Russia’s still moving a lot of pieces around, including “command and control, artillery, other enablers into the Donbas,” the Pentagon said. “We still believe that the Russians are doing a fair amount of shaping” with air and artillery strikes along front line regions, the official said.  

Related reading: “Lethal darts were fired into a Ukrainian neighborhood by the thousands,” via the Washington Post’s Alex Horton, reporting Monday from Bucha, outside Kyiv.

New: At least four U.S. planes with equipment for Ukraine landed in Europe on Sunday, and another is expected soon. Together, that’ll be five flights in about as many days since President Joe Biden announced this latest $800 million tranche of weaponry for Kyiv.  

President Joe Biden rang up allies this morning to discuss “continued support for Ukraine and efforts to hold Russia accountable as part of our close coordination,” according to the White House’s schedule for the day. 

Big picture consideration: Russia’s invasion of Ukraine could signal “The Return of Conquest,” as Minnesota professor Tanisha Fazal warns in the latest issue of Foreign Affairs—though she ends that title with a question mark. 

Why does it matter? For starters, Fazal argues, “If the global community allows Russia to subsume Ukraine, states may more frequently use force to challenge borders, and wars may break out, former empires may be reinstated, and more countries may be brought to the edge of extinction.” Even should Ukraine somehow emerge victorious, “A resurrected Ukraine might deter future would-be conquerors from attacking the country,” she writes. “But globally, aspiring invaders would draw a clear lesson: it is possible to get away with territorial conquest.” Read on, here.

Additional reading: 

• “Russian invasion damaged up to 30% of Ukraine's infrastructure, says minister,” via Reuters, reporting Monday; 
• “In Ukraine’s South, Russian Occupiers Tighten the Screws,” via the Wall Street Journal’s Yaroslav Trofimov, reporting from Dnipro; 
• “Stolen AirPods give away Russian retreat positions,” via the UK’s Times, reporting Monday; 
• “Russia, Ukraine air dueling videos of detainees seeking prisoner swap,” via the Washington Post, reporting Monday; 
• “The Russian ambassador is Washington’s least popular man,” via Politico, reporting Monday; 
• And ICYMI, “Ukraine’s Draft Dodgers Face Guilt, Shame and Reproach,” via the New York Times, reporting April 10 from Moldova.

From Defense One

US to Train Ukrainians to Use Their New 155mm Howitzers // Caitlin M. Kenney: The donated artillery is expected to arrive within days—but there are reports that the Russian assault in the east is already starting.

Air Force Raises a Last Glass to the Final Doolittle Raider  // Tara Copp: The children of Lt. Col. Dick Cole say farewell to the last of 80 men who flew the historic 1942 mission.

Give Ukraine Better Air Defenses  // Hlib Kanievskyi and Olena Tregub: If other European capitals want to avoid Kyiv’s fate, they must arm Ukraine with better defenses against Russia’s missile onslaught.

Welcome to this Tuesday edition of The D Brief, brought to you by Ben Watson with Jennifer Hlad. If you’re not already subscribed to The D Brief, you can do that here. On this day in 1985, FBI agents surrounded the training compound of a far-right militant group of white supremacists known as the Covenant, the Sword, and the Arm of the Lord, which had declared war on the “corrupt” U.S. government two years prior. The group later surrendered when its followers realized they were outnumbered by the FBI and that no other far-right militants were going to save them.

New: Vice President Kamala Harris says the U.S. will stop shooting down satellites in space as part of a deliberate effort to introduce at least some long called-for rules to the space domain.
Rewind: You may recall Jeffrey Lewis of the Middlebury Institute of Strategic Studies in Monterey explained why no norms in space is a problem back in our March 2020 Defense One Radio podcast. One year prior, India shot down a satellite to demonstrate its capability; but that shot—similar to other 21st-century demonstrations or missions by China, the U.S., and nearly half a dozen by Russia—left a dangerous trail of debris in orbit around the planet.
Russia most recently shot down a satellite this past November. The Stockholm International Peace Research Institute, or SIPRI, ran a commentary shortly afterward entitled, “Russia’s anti-satellite test should lead to a multilateral ban.”
VP Harris: “We have consistently condemned these tests and called them reckless. But that is not enough,” she said Monday evening at Vandenberg Air Force Base, Calif. “Today we are going further. I am pleased to announce that as of today, the United States commits not to conduct destructive direct-ascent anti-satellite missile testing.”
“We are the first nation to make such a commitment,” Harris said. “And today, on behalf of the United States of America, I call on all nations to join us.”
Jeffrey Lewis: “This is an important step—one that the Obama Administration pledged to take, but didn’t… So, like most things, this is a case of better late than never, even if the current moment doesn’t seem promising for any sort of agreement.”
Bonus explainer: Lewis went on NPR back in 2007 to argue for just this sort of moratorium after China’s ASAT test that year.

No more mask mandate on U.S. public transportation. A federal judge struck down a Centers for Disease Control and Prevention decision to require masks on airplanes, trains, and buses, according to Judge Kathryn Kimball Mizelle of Florida’s 59-page decision. White House officials said they’re considering their options for appeal, but have not yet signaled they intend to pursue that, according to the New York Times.
By the way: U.S. Army Chief Gen. James McConville just tested positive for Covid. “He is experiencing very mild symptoms similar to seasonal allergies and is currently working remotely while adhering to all CDC protocols,” his public affairs team announced Monday. The chief is vaccinated and boosted twice over.
For your ears only: Librarian-turned-reporter Brandy Zadrozny of NBC News just produced a podcast all about a nurse who fainted after her Covid vaccine in 2020. “She's fine,” Zadrozny tweeted Monday previewing the podcast, “but the internet decided she was dead.” Her new podcast, “Tiffany Dover Is Dead*,” dives into how the conspiracy theory “started, why it spread, and who it hurt.” Start listening here.

With an eye on Pyongyang, the United States and South Korea reaffirmed their commitment to deter North Korea’s “escalatory actions,” Reuters reported Monday, two days after North Korea reportedly tested a new kind of tactical guided weapon.
“It is extremely important for the United Nations Security Council to send a clear signal to [North Korea] that we will not accept its escalatory tests as normal,” U.S. Special Representative Sung Kim said after meeting with South Korean officials.
The U.S. and South Korean militaries also kicked off annual joint military exercises on Monday, to the chagrin of North Korea, which views such exercises as rehearsals for an invasion, according to the Associated Press. 

Developing: Three explosions rocked a high school in western Kabul, killing at least six people on Tuesday, according to Reuters; however, details are unclear and official statements are difficult to corroborate under Taliban control. 

And lastly: China says it just signed a formal security pact with the Solomon Islands, and Beijing officials announced the signing of this once-secretive pact as U.S. officials arrived for separate talks, Reuters reports—while emphasizing Chinese officials have shared no details about the signing venue or timing. 
Get your bearings: Agence France-Presse takes a 30,000-foot view of the islands in a sort of abbreviated explainer map you can find here.
This could be bad news for Australia, which is concerned the pact may be “a step towards a Chinese military presence less than 2,000 km (1,200 miles) from Australia,” according to Reuters. However, the prime minister of the Solomon Islands reportedly told his country’s parliament that the agreement would not include a Chinese military base. More here.