In a flurry of unilateral executive actions, Mr. Trump revived disputed claims of broad presidential authority from his first term — and made some new ones. Court battles seem likely.

© Doug Mills/The New York Times

Republicans are hunting for ways to pay for President Trump’s expensive plans while avoiding a freakout on Wall Street.

© Doug Mills/The New York Times

Automakers and even some Republicans may fight to preserve funds, and environmental activists will likely sue, but some experts said that some changes may not survive legal challenges.

© Philip Cheung for The New York Times