On Monday night, at a lavish state banquet, the queen, exchanging toasts with Mr. Trump, pointedly took note of the institutions, like NATO, that Britain and the U.S. helped create after World War II to prevent another war.

Next: Demonstrations are expected on Tuesday as Mr. Trump meets with Prime Minister Theresa May. He will visit France later in the week for D-Day commemorations.

Photos: See the royal collection gift review, the arrival of the president’s helicopter and more.

History: Trump’s love affair with the royal family dates back to his mother, a Scottish immigrant who was enthralled by the queen. Our correspondent took a look back at the president’s interactions with the royal family.

Antitrust troubles snowball for big tech

The U.S. government is stepping up its scrutiny of the world’s biggest tech companies, as regulators divvy up oversight of the Silicon Valley giants and lawmakers move to investigate whether they have stifled competition.