When Sheikh Tamim bin Hamad al-Thani, the emir of Qatar, hosts President Trump at a lavish dinner at his palace in Doha on Wednesday evening, it will be the culmination of a successful charm offensive by the Gulf emirate that now appears likely to include the promise of a luxury jetliner to Mr. Trump — with no strings attached.

The president, who has described the emir as a “great gentleman” and a “friend of mine,” is granting Qatar the honor of hosting one of the first foreign visits of his second term. As for the plane, the president says he would be “stupid” not to accept such a nice gift despite loud objections, not only from Democrats but from some of his most fervent MAGA supporters.

It is a dramatic turnaround for a small Persian Gulf country that Mr. Trump derided eight years ago as “a funder of terrorism at a very high level.” At that time, he cooperated with Qatar’s bitter rivals in the region — who imposed a punishing blockade on Doha — in calling for an end to what he described as the country’s “extremist ideology.”

Since then, Qatar has continued to try and transform its reputation in the global community, in part by spending millions of dollars on lobbyists in Washington and other capitals. Among those lobbyists was Pam Bondi, now Mr. Trump’s attorney general.

A big part of Qatar’s image makeover was its hosting of the FIFA World Cup in 2022. A year later, when Hamas-led terrorists attacked Israel and set off months of brutal war in Gaza, Qatar became a crucial line of communication between the militant group and Israel.

“What Qatar is trying to do today is not only bask in its wealth and be delighted by the fact that Trump wants to visit, but also sort of burnishing itself for being able to say, ‘Yes, we’re back,’” said Simon Henderson, a senior fellow at the Washington Institute for Near East Policy.