A North Korea expert told Fox News Digital that the United States "can never take their eye off" Kim Jong Un and the Korean Peninsula after Pyongyang test-fired a missile this week amid the ongoing conflict with Iran.
The launch of the short-range ballistic missile — which Japan said landed in the waters off North Korea’s east coast — unfolded Thursday ahead of joint military exercises to be conducted by the U.S. and South Korea later this month.
"There's this unsettled conflict on the Korean Peninsula. And Kim Jong Un, a very unpredictable leader that seeks attention, that is something the United States can never take their eye off," retired Navy Rear Adm. Mark Montgomery, a senior fellow at Foundation for Defense of Democracies, told Fox News Digital on Friday.
"So we have all these challenges in the Middle East, these challenges with Russia and Ukraine, these challenges with China pressuring and trying to coerce Taiwan. You can never forget that the North Korean challenge to South Korea is sitting right there, and there are no constraints on Kim Jong Un," Montgomery added. "There's no version of an empowered elite or a population or a military that could unseat him. So we should always keep our eye on him, pay attention to him, and make sure we're constantly deterring any provocative behavior."
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U.S. Indo-Pacific Command said following North Korea’s launch on Thursday that, "We are aware of the missile launch and are consulting closely with our allies and partners."
"Based on current assessments, this event does not pose an immediate threat to U.S. personnel or territory, or to our allies," it added. "The United States remains committed to the defense of the U.S. homeland and our allies in the region."
Montgomery said Friday that "whenever North Korea does a ballistic missile launch, you have to think there's any of three countries that could be the intended recipient of the message — it could be the United States, it could be South Korea, it can be Japan or it could be a mix."
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He described how Japan recently test-fired a Tomahawk cruise missile in late July, with the help of the U.S. Navy.
"Maybe this could be a signal back to them," Montgomery said. "South Korea and the United States are about to start the Ulchi Freedom series of exercises... the most robust series of exercise we have there every August when conducted."
Montgomery also said "recently there have been a lot of reports the United States has expended a large percentage of its theater ballistic missile defense weapons... Patriot 3 and THAAD, in the conflict in Iran."
"Those are the kind of defensive systems that might be used against this weapon. Also, there's U.S. Navy standard missiles, which also have been depleted in the Middle East. In all those cases, North Korea could be signaling to any of the three countries or a mix of the three countries that we're still relevant, we matter, and you need to pay attention to us," he said.
Fox News’ Liz Friden contributed to this report.