President Donald Trump may have tasked his second-in-command JD Vance with selling the rebrand of the GOP’s tax law, but what the vice president is really concerned with is gratitude.

More specifically, he’s fixated on people who he believes are insufficiently grateful for what the United States has provided for them.

Take, for instance, former Vice President Kamala Harris. She wasn’t fit to lead the country, Vance said on the campaign trail, because she wasn’t “grateful for it.”

Vance famously clashed with Volodymyr Zelenskyy in the Oval Office in February over the Ukrainian leader’s failure to grovel to Trump for all the aid the U.S. had provided Zelenskyy’s country during its ongoing war against Russia.

“Have you ever said ‘thank you’ once?” the VP said.