The Ulchi Freedom Shield exercise began on August 17, the day President Trump said out loud that he wanted such drills cut back. The exercise runs "11 days (Aug 17-27)" and involves "18,000 South Korean soldiers," according to Al Jazeera [1]. It started on schedule.
Trump's objection was blunt. He said he is "not happy with the fact that the United States has, long ago, agreed to participate in Joint Military Exercises with South Korea," called the drills "costly," and described North Korea's Kim Jong Un as "unthreatening and respectful" [1]. He also folded in a grievance about a separate ask, saying he had invited Seoul to "join us in the Denuclearization of the Islamic Republic of Iran, and they said, 'No thanks!'" [1].
On the right, that mix of a promised drawdown and kind words for Pyongyang has been packaged into a single line: Trump forms alliance with North Korea. Set the record beside it. Two facts do the work. The exercise Trump complained about still ran, on schedule, with 18,000 South Korean troops, and the ally in question said so itself: South Korea's Ministry of Defence stated the exercises would "proceed as previously notified and scheduled" [1].
A lighter drill tempo and warmer language toward Kim are real, and they are worth watching. They are not a treaty. An alliance is a standing mutual-defense commitment with a partner, and the one the United States holds in this theater is with South Korea, the country whose soldiers were in the field this week. Nothing in the reporting shows a defense pact with North Korea, a change in the US-South Korea treaty, or a withdrawal of the drills that actually happened.
The accurate summary is narrower than the slogan and more consequential than it lets on. Trump wants the exercises reduced, he is courting Kim rhetorically, and Seoul is publicly holding the line on the alliance and the schedule at the same time.