At an event to launch his presidential campaign, former Vice President Mike Pence landed his strongest attack yet on his one-time boss, Donald Trump—while also trying to claim credit for some of the Trump Administration’s record. Speaking to a crowd in Iowa, Pence took aim at Trump’s wavering stance on abortion, saying Trump was “retreating from the cause of the unborn,” and also railed against his incitement of the Jan. 6 riots. “The American people deserve to know that on that day, President Trump also demanded that I choose between him and the Constitution,” Pence said. “I chose the Constitution, and I always will.” But Pence also boasted of his role in the “Trump-Pence administration,” trying to leverage his work under Trump while distancing himself from Trump personally. That balancing act may prove difficult for Pence as he enters a crowded Republican primary field with polling numbers dwarfed by Trump’s.