Elon Musk, the tech billionaire and one of President Trump’s top advisers, on Monday accused Senator Mark Kelly, Democrat of Arizona, of being a “traitor” after he visited Ukraine and said the United States should keep supporting its war against Russia.
Mr. Kelly, a former NASA astronaut and Navy pilot who flew combat missions during Operation Desert Storm, visited Ukraine over the weekend, meeting with members of the Ukrainian military, nurses and others, concluding in a social media post that what he saw “proved to me we can’t give up on the Ukrainian people.”
In reply, Mr. Musk wrote: “You are a traitor.”
And with that, one of the president’s powerful supporters equated a policy disagreement with one of the most serious crimes against the United States.
On Monday, Mr. Kelly hit back at Mr. Musk.
“Elon, if you don’t understand that defending freedom is a basic tenet of what makes America great and keeps us safe, maybe you should leave it to those of us who do,” he wrote on X, which Mr. Musk owns.
Their public spat comes less than two weeks after Mr. Trump berated President Volodymyr Zelensky of Ukraine in the Oval Office, telling him that he had not been grateful enough for U.S. support in its war against Russia’s invasion and seeking to pressure him into making a peace deal on U.S.-dictated terms.
Mr. Kelly’s original posts also directly accused President Trump of “trying to weaken Ukraine’s hand” in his pursuit of a peace deal between Kyiv and Moscow. On Monday, Marco Rubio, the secretary of state, said Ukraine would have to be willing to give up territory in any peace deal with Russia.
Mr. Trump’s antagonism toward Ukraine while bolstering Russia has been criticized by Democrats as well as some Republicans. During the Biden administration, members of both parties in Congress approved sending billions of dollars in aid to Ukraine as it fought Russia’s invasion.
Mr. Musk and Mr. Kelly have butted heads before, though Mr. Kelly once served as a member of an independent safety advisory panel for SpaceX, another company owned by Mr. Musk.
In February, Mr. Musk said during a joint interview with Mr. Trump on Fox News’s Sean Hannity Show that NASA astronauts had been left stuck aboard the International Space Station “for political reasons.” Mr. Musk also called Mr. Kelly a “Dem donor shill” in a post criticizing him, his twin brother, Scott Kelly — also a former astronaut who once commanded the International Space Station — and Andreas Mogensen, a Danish astronaut who had also criticized Mr. Musk’s comments.
“Hey @ElonMusk, when you finally get the nerve to climb into a rocket ship, come talk to the three of us,” Mr. Kelly retorted.
Theodore Schleifer contributed reporting.
