Trump reposted a call for South Korean Patriot missiles to go to Ukraine. Will it actually get there?

Amidst U.S. President Donald Trump's call for South Korea to dispatch troops to Iran, the president has also retweeted an article requesting that Seoul send its homegrown Patriot equivalent to Ukraine.

While Trump said nothing himself, he did post the headline and link to a Washington Post column titled "How Trump can help Ukraine make its own Patriot missiles" to his social media account on Sept. 4.

With the column urging a sale of the Cheongung-II air defense system, South Korea’s policy of keeping weapons out of active war zones is facing a fresh test.

Conservative People Power Party (PPP) Rep. Yu Yong-weon has publicly urged the government to consider a sale, but many in the Korean military sector are skeptical of the move, taking into consideration both the plausibility of the plan and whether it should happen in the first place.

Yu seems to be nearly alone among both prominent lawmakers and government officials. When asked whether the Blue House's position had shifted at all since Yu began pressing the case, he said, "There is no change."

Filling in for the Patriot

The U.S. push is a supply problem before it is a diplomatic one. Lockheed Martin’s PAC-3 line cannot keep pace with what the wars in Ukraine and Iran have consumed, and a new Patriot order takes four to six years to arrive.

The Cheongung-II, developed by the Agency for Defense Development with LIG D&A, Hanwha Systems and Hanwha Aerospace and marketed at home as the Korean Patriot, is the readiest substitute anyone has identified. It engages aircraft and ballistic missiles at ranges up to roughly 50 kilometers (31 miles), and each interceptor costs about $1.1 million against $3.7 million for a PAC-3, according to the Financial Times. Roughly a third of the price, rolling off a line that is still expanding.

The Washington Post column was written by Marc Thiessen, a fellow at the American Enterprise Institute and a former speechwriter for President George W. Bush. Licensed Patriot production inside Ukraine would take years, he argued, while the interceptor shortage is immediate and South Korea has a system that could fill the gap now.

LIG D&A has booked a combined 12.6 trillion won ($9.4 billion) in Cheongung-II contracts with the United Arab Emirates (UAE), Saudi Arabia and Iraq as of early September.

It also has a combat record, and a recent and good one at that.

On Feb. 28, Iran fired roughly 130 ballistic missiles at the UAE, where Cheongung-II batteries operated alongside Patriot and Arrow systems. Rep. Yu, a member of the National Assembly’s National Defense Committee, said in March that two Cheongung-II batteries fired about 60 interceptors and hit 96 percent of their targets, citing sources familiar with the engagement.

Yu is considered one of the most vocal advocates for a transfer, and his case rests less on what Ukraine would receive than on what South Korea would gain. Russian forces have been firing North Korean ballistic missiles at Ukrainian cities for more than a year.

The KN-23 and KN-24, as the two most common types are designated in the West, are short-range ballistic missiles that Pyongyang would fire at the South in a war, and no South Korean air defense system has ever engaged one.

"I understand that Ukraine has conveyed to South Korea, directly and indirectly, that it would hand over engagement data on the KN-23 and KN-24 if Cheongung-II systems were provided," the lawmaker said in written answers to questions on Sept. 11. He described the account as secondhand. The Ministry of National Defense and the Defense Acquisition Program Administration did not respond to requests for comment.

Yoo Hyon-joo, a professor of political science and diplomacy at Hankuk University of Foreign Studies, is unconvinced that the data is worth the exposure.

"It has already been demonstrated in the UAE," she said during a phone interview on Sept. 10, adding that hardware sent into Ukraine can be taken apart, and what Ukraine learns can reach Russia.

Rep. Yu has heard the objection.

"That is a legitimate concern, but receiving real combat data on the KN-23 and KN-24 would be the greater gain," he said.

What is actually stopping it

No South Korean statute bars defense sales to countries at war. The restriction runs through licensing. The Public Notice on Trade of Strategic Items, issued under the Foreign Trade Act, conditions export permits on peaceful end use, and Article 57 of the Defense Acquisition Program Act requires government permission for defense exports.

Successive governments have summarized the result the same way: no lethal weapons to areas of conflict.

South Korea has sent Ukraine body armor, helmets, rations and medical supplies since 2022 under the same policy, and an air defense missile destroys an incoming missile rather than a person. When the Foreign Ministry responded on Aug. 10 to Ukrainian President Volodymyr Zelensky’s request for South Korean air defense, its statement said only that defense matériel transfers follow domestic law and policy. The phrase about lethal weapons, standard in such statements for four years, was absent.

Choi Gi-il, a professor of military studies at Sangji University, said during a phone interview on Sept. 10 that the statement papers over how the rules are written.

"The laws strongly limit weapons exports to areas of international conflict or active war, but they are discretionary provisions, not mandatory ones," he said. "In practice, they work as if they were mandatory."

Exports of this kind need political consent as much as legal clearance, according to Prof. Choi, and governments have treated the discretionary language as binding because the alternative is being pulled into someone else’s war.

Prof. Choi pointed to the 155-millimeter artillery shells that reached Ukraine by way of the United States under former President Yoon Suk Yeol, saying, "Throughout President Yoon Suk Yeol’s term, the government denied to the very end that any such thing had happened."

Rep. Yu reads the same statutes and arrives somewhere else.

"Depending on how the Foreign Trade Act and related rules are interpreted, there may be some constraints, but consent from the National Assembly is not required," he said.

Hankuk University's Prof. Yoo argues that the disagreement is itself the answer.

"The law has always been there," she said. "The question is how you interpret it to justify the foreign policy you have already chosen. This is not a legal problem."

The comparison that keeps surfacing is the Persian Gulf. Saudi Arabia and the UAE both took deliveries while under missile attack, which Ukrainian commentators have raised as evidence of a double standard.

An industry source with direct knowledge of Cheongung-II production who asked for anonymity said the sequence is what separates the cases.

"It was a request to bring forward volumes that were already under contract," the industry source said. Those contracts were signed well before the fighting started, and no comparable contract exists with Ukraine.

The stockpile question

Rep. Yu is not proposing that South Korea strip its own batteries. He said he has in mind a commercial sale of newly produced units rather than a transfer of active-duty systems, not a donation.

"From what I have gathered unofficially, LIG D&A has the production capacity to absorb a volume of exports for Ukraine," he said.

"Our weapons are all sold government-to-government," the industry source said, which is why the company takes no position on where they go. Guided weapons are largely built by hand rather than stamped out, the source said, and output figures are withheld on principle.

"Disclosing production capacity is directly connected to a country’s ability to sustain a war, so the manufacturer cannot reveal it," the source said. "The first place anything the defense industry builds is meant to go is the defense of this country."

Prof. Choi doubts the arithmetic holds. Contracted volumes for Saudi Arabia and others are still backlogged, he said, and any new order would join the back of that line.

"By the time anything contracted now was actually delivered to Ukraine, the war would already be over," he said. The International Institute for Strategic Studies assessed in March that LIG D&A was struggling to meet demand and might need nine to 12 months to expand capacity.

There is a second detraction. South Korea would be handing over air defense at a moment when its own coverage is thinner than usual, and the argument Washington uses to keep its Patriots at home applies just as neatly in Seoul.

"Just as the United States worries about the gap it would create in its own defenses, South Korea would face the same gap," Prof. Yoo said.

Two months left

Behind all of it sits Moscow. South Korea’s remaining trade with Russia, and the Kremlin's deepening alignment with Pyongyang, are the constraints officials rarely state out loud.

A legal adviser at a Seoul law firm who advises on defense exports, also speaking on condition of anonymity, put it in plain transactional terms. The Gulf sales carried a justification the public could follow, since South Korea buys much of its energy from the region. Ukraine, the legal adviser said, offers nothing comparable in return.

The Hankuk University professor's objection is about consistency.

"You have told the public for years that the law does not allow it," she said. "Turning around and saying it is allowed now could backfire."

A shift that size needs a change large enough to explain to voters, she said, and there has not been one.

Simply put, "There is no need to be swayed by every post Trump puts up."

Seoul has still not been formally asked for anything. There is no confirmed purchase request from Ukraine and no known license application submitted to the government.

BY KIM MIN-YOUNG [[email protected]]