Democrats Turn to Their National Security Go-To for Trump Assassination Inquiry

Representative Jason Crow, a Colorado Democrat and former Army Ranger, had just ordered his second martini at a bar in Bucharest, Romania, when Representative Nancy Pelosi, the former speaker, called him with an urgent question: How quickly could he get to Ukraine?

It was April 2022, weeks after Russia had invaded Ukraine and touched off an international crisis, and two Republican lawmakers had rushed to be the first to travel to the besieged country. Now Ms. Pelosi wanted to quickly arrange her own visit — and she wanted Mr. Crow, whose national security background distinguished him in his party, to come with her.

A late-night phone call from Ms. Pelosi to Mr. Crow would have been improbable when he first came to Congress in 2019. Hailing from a competitive district in Colorado, he had run as a centrist and avowed detractor of the liberal Ms. Pelosi, and after he knocked off a Republican incumbent he pledged that he would not vote for her for speaker.

But since then, his credentials — including three tours of duty in Iraq and Afghanistan and a Bronze Star, as well as a law degree and a background in private-sector investigations — have made Mr. Crow a go-to lawmaker for Democratic leaders on difficult national security issues.

Ms. Pelosi tapped him in 2019 to manage the first impeachment of President Donald J. Trump. He was part of the whip operation to rally support for legislation to send tens of billions of dollars in aid to Ukraine. He was selected as the top Democrat on a subcommittee investigating the Biden administration’s botched withdrawal from Afghanistan.

And last month, he was named the senior Democrat on a bipartisan task force to investigate the attempted assassination of Mr. Trump at a campaign rally in