After a tense cabinet meeting this month during which Secretary of State Marco Rubio and other department heads criticized Elon Musk’s sweeping dismissals of federal workers, President Trump told Mr. Musk to use a “scalpel” rather than a “hatchet” when recommending future job cuts.

Last Friday, employing his own definition of “scalpel,” Mr. Trump gutted seven government entities, including the U.S. Agency for Global Media, which presides over Voice of America and other international broadcasters. Meantime, Mr. Musk’s Department of Government Efficiency imposed a month-long funding freeze on VOA. On Saturday nearly all VOA journalists were placed on administrative leave with pay, as was its director.

Mr. Musk signaled his interest in shutting down VOA in February, when he tweeted an attack on it and Radio Free Europe—organizations established to emphasize democratic values in countries where free press is threatened. In a play on Radio Free Europe’s name, he tweeted: “Europe is free now (not counting stifling bureaucracy). Hello??” Does Mr. Musk think that Russia, to which Radio Free Europe broadcasts 24 hours each day, is free? He then broadened his attack: “Nobody listens to them anymore,” he charged. “It’s just radical left crazy people talking to themselves while torching $1B/year of US taxpayer money.”

Mr. Musk doesn’t know what he’s talking about. Voice of America has an annual budget of about $270 million, and it reaches a weekly audience of about 360 million around the world. In Africa, its audience has expanded from 78 million to almost 94 million in the past two years. Eliminating VOA’s Africa division would surrender the battle of ideas to Chinese and Russian propaganda outlets vying for influence in a region whose population is projected to double in the next 25 years.

VOA is one of the few fact-based news sources reaching China. In moments of crisis, such as the 1989 Tiananmen Square massacre, millions of Chinese have relied on VOA for the truthful accounts they can’t find in their own country’s media. VOA also works to counter the incessant disinformation war that China is waging against the U.S. No wonder state-run Chinese media celebrated the announcement that VOA’s journalists would no longer be permitted to do their jobs.

Similarly, Iranian media and Ayatollah Ali Khamenei’s chief advisers gloated over the news that the Trump administration was gutting VOA, effectively suspending its broadcasts into Iran. Despite the Iranian government’s efforts to block these broadcasts, the Iranian audience for them has expanded dramatically in recent years. VOA’s Persian website had 223 million visits last year. Mr. Trump’s March 4 address to Congress got 1.3 million video views in Iran through VOA.

China spends more than 10 times as much on international media activities as VOA spends. Mike Waltz, Mr. Trump’s national security adviser, has long advocated a hard-line stance toward Beijing. What would he think of America’s surrender in the information war with China? And what view does Elbridge Colby, Mr. Trump’s nominee to serve as undersecretary of defense for policy, take? Mr. Colby has written that “the top external threat to America is China—by far.”

VOA has made mistakes, as has every media organization, and reasonable reforms are long overdue. A scalpel-rather-than-hatchet strategy could trim the U.S. Agency for Global Media’s bureaucracy, eliminate the overlap between VOA and the regional broadcasters such as Radio Free Europe, and improve editorial oversight.

An effective media campaign helped Mr. Trump return to office. He should understand the power of persuasion to shape public opinion that promotes his goals. But when it comes to international affairs, he seems to have a blind spot. Mr. Trump apparently believes in using a combination of carrots and sticks to change the policies of other countries’ leaders but not in using targeted information to shape public attitudes overseas.

Public opinion matters, which is why autocrats work so hard to manipulate it. If their citizens have no access to alternative views, autocrats are more likely to succeed—with less effort and cost. The U.S. shouldn’t play into their hands. We should mend, not end, the Voice of America.