Words matter. We need them to communicate meaning, and so others will understand the basis for our thoughts and actions. And when it comes to war, words can kill; presidents do not have the luxury of imprecision, carelessness, or dishonesty. In a military context, words must be precise, and their meaning understood. In the aftermath of the Syrian strike and the first combat use of the “Mother of All Bombs,” the President spoke in ways that should concern Americans.

Donald Trump said he has given the military “total authorization.” That may sound great, but “total authorization” has no meaning. The military’s dictionary, (yes, it has its very own) includes “diplomatic authorization” and “letters of authorization,” but does not include “total authorization.” Perhaps Mr. Trump chose a non-existent term when he actually meant to say that he, as the commander in chief, had issued an order giving the military specific authorization to conduct operations limited in time and space.

Alternatively, perhaps Mr. Trump simply wanted Americans to know that he will exercise less oversight and control of the U.S. military as compared to his predecessors. Without clarification, we cannot be sure. There are at least fifteen different types of orders that the President, Secretary of Defense and military commanders can issue to those under their charge. They cannot, however, issue “total authorization.”

In the same vein, Mr. Trump’s characterization of recent military operations as “so successful” reveals that he has little idea what military success looks like. Trump’s crowing over a single missile strike against Syria or the use of the “Mother of All Bombs” in Afghanistan suggests that he equates action and aggression with success. As history has made clear, nothing could be further from the truth.

The reality is that wars and civil conflicts are complex; successfully ending them is difficult. Though the U.S. military can defeat any adversary, the past 16 years provide overwhelming evidence of the profound limits on military power when foreign leaders fail to convert American-made battlefield gains. Iraq and Afghanistan are less stable today than they were before the U.S. invaded. Terrorism has skyrocketed in response to America’s war on terror. And, despite U.S. forces having killed so many, the number of Islamist-inspired fighters has more than tripled since 2001.

It would be tragic if it took Mr. Trump the next four years to learn that a single military strike is, by itself, meaningless unless it helps achieve a broader objective. One missile strike will not change the course of the war in Syria, nor will one large bomb seal the fate of the insurgents in Afghanistan.

Moreover, calling such efforts “success” misleads the American public about the true state of affairs. Too many claims of “success” will strain the currently weak bonds of trust between Trump and the public, who have already tired of false promises of progress and victory made by past presidents. Premature cries of success also risk convincing American allies that Mr. Trump will change course on foreign policy. Bolstered by the strikes, many in Syria and Afghanistan have renewed hope that the United States will intervene more aggressively, which runs counter to most of Donald Trump’s campaign promises to focus on America first.

President Trump owes the nation — and the world — more careful language. Trump’s empty words may thrill his supporters, but they will not defeat the Islamic State or bring peace to a troubled region. If the American public is to trust him and intelligently support his foreign policies, especially with lives on the line, he must communicate coherently. The president should weigh his words before he speaks, provide clear explanations for his actions and measured assessments of progress. In short, Trump’s words need to mean exactly what they seem to mean.