North Korea's latest rocket launches are a symbolic display of disapproval of military cooperation between South Korea, the U.S., and other allies in Asia.

North Korea launched several ballistic missiles toward the Yellow Sea on Monday afternoon, Seoul's military said, on the first day of a large-scale joint U.S-South Korea military exercise on the Peninsula.

For the Trump administration, it was a duo of firsts on the Korean Peninsula on Monday: the first South Korea-U.S. joint military drills and North Korea’s first missile barrage.