The SpaceX CEO seemed to parrot Trump's nickname for Biden.
Last week, SpaceX successfully completed the first all-civilian spaceflight with the successful splashdown of its Inspiration4 mission.
Shortly thereafter, the company and CEO Elon Musk racked up praise and congratulations from government officials including NASA Administrator Bill Nelson and spaceflight industry competitors including Blue Origin CEO Jeff Bezos.
But apparently that wasn't enough for Musk, who took a jab at President Biden on Twitter for not yet offering a congratulation of his own.
Musk mocked Biden on Sunday afternoon after a Twitter user called out the President for not yet acknowledging the mission's success or the money that it raised for St. Jude Children's Research Hospital, asking for theories on Biden's silence.
"He's still sleeping," Musk replied, in what appears to be a reference to former President Trump's nickname for his successor, "Sleepy Joe."
This isn't the first time Musk has taken a jab at Biden. Just last week he replied to a meme depicting the massive union United Auto Workers as a parasitic alien that had latched onto Biden, mirroring his earlier frustration at a new law that supports unionized automakers.
Hand That Feeds
SpaceX has an overall cozy relationship with the federal government, which CNBC notes has awarded plenty of contracts to the private spaceflight company. A mildly-rude tweet is unlikely to change that, since SpaceX has proven itself to be capable of missions to the International Space Station time and time again and is NASA's favored company to develop a Moon lander.
The White House didn't respond to CNBC's request for comment. If we may speculate, Biden's spokesperson was probably too busy rolling their eyes.
READ MORE: Elon Musk mocks President Biden after SpaceX completes first all-civilian mission [CNBC]
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