The first summit meeting between U.S. President Donald Trump and ROK President Lee Jae-myung on Monday nearly veered off course before it began, exposing just how vulnerable the U.S.-ROK alliance is to Trump’s impulsive messaging and the disinformation networks surrounding him.

A last-minute social media post from Trump just hours before the scheduled meeting set off a scramble in both capitals, when the U.S. president suggested, without evidence, that South Korea was experiencing a “purge or revolution,” and added that “we can’t have that and do business there.”

Though Lee’s carefully calibrated response turned a potential rupture into a contained