In a surprise decision this May, the U.S. Defense Department canceled a planned deployment of thousands of troops to Poland, a NATO ally that has cultivated strong ties to U.S. President Donald Trump.

Within days, Trump seemingly offered good news for Warsaw: “I am pleased to announce that the United States will be sending an additional 5,000 Troops to Poland,” Trump wrote on Truth Social, framing the decision as inspired by the 2025 election of Polish President Karol Nawrocki, a Trump ally.

“I ​thank U.S. President Donald J. Trump for his friendship toward Poland and for the decisions whose practical dimension ​we see very clearly today,” Nawrocki wrote in response.

In July, Polish Defense Minister Wladyslaw Kosiniak-Kamysz said officials from the U.S. Embassy in Warsaw had told him that U.S. forces would take the place of the canceled rotation “in the coming weeks.” But nearly four months later, those troops still haven’t arrived, and the Pentagon has not made any public statements about when they might be coming.

While it’s unclear what specifically may be preventing a faster deployment, the whiplash hints at the difficulty in executing the administration’s abrupt policy pivots and the reputational cost incurred—as well as the limits of what even a pro-U.S. country such as Poland can expect from its diplomatic efforts.

For Poland, which borders Russia’s exclave of Kaliningrad, the presence of U.S. forces serves as a security guarantee against potential Russian attacks. But the specific number of troops is also “symbolic” for Poland, said Philip Bednarczyk, the Warsaw office director for the German Marshall Fund. “If they remove troops from Poland, that’s not what we were shooting for here,” he said.

The Pentagon did not provide a response to questions submitted by Foreign Policy. A Polish official, speaking on condition of anonymity to discuss sensitive negotiations, said that planning for the troop deployment that Trump announced is continuing but that it was “difficult to say” when an announcement might be made.

“There is an ongoing diplomatic Polish offensive in D.C.,” said a former Polish diplomat, also speaking on condition of anonymity to discuss the sensitive conversations. “I think efforts are necessary also in case of no deployment and no success, because Polish public opinion will then have a clear picture whose fault it was.”

The delay comes despite Poland’s significant investments in defense, its large purchases of expensive U.S. weaponry, and the personal relationship between Trump and Nawrocki. Both U.S. Defense Secretary Pete Hegseth and Pentagon policy chief Elbridge Colby have called Poland a “model ally.”

There are likely a number of technical challenges to sending the troops that Trump promised, said John Ferrari, a senior fellow at the American Enterprise Institute and a former U.S. Army major general.

For one, the Army only has so many armored units, making it difficult to send an alternate unit on short notice. For another, the Army is likely stretched by the operational costs of deployments associated with the war in Iran. “Part of this may be [that] they just don’t have the money to send them over there,” Ferrari said.

Still, Ferrari noted that the Pentagon had missed an opportunity to clarify that forces would return to Poland: “Even with the sort of deliberative processes, that’s a good amount of time to at least announce it,” he said.

In the meantime, the lack of clarity hurts the reputation of the United States, said the former Polish diplomat. “The credibility of the United States government is decreasing. It’s become frustrating in the context of repeated Pentagon officials’ description of Poland as a ‘model ally.’”

Congress has also not been pleased. “The inaction over the last three months is negligence.” Rep. Don Bacon wrote on Aug. 30, after earlier threatening to hold up billions in military funding over the matter.

Another possible explanation is that the Pentagon is waiting for the conclusion of a review of its force numbers in Europe, which is set to be submitted to Trump in December. That review could significantly cut overall troop numbers, but might shift more forces to Poland, as the review is proceeding concurrently with negotiations over expanding the U.S. military’s permanent presence in the country. Polish Foreign Minister Radoslaw Sikorski said in September that the discussion involved the possible construction of permanent facilities for as many as 10,000 U.S. troops.

“It’s probable that this troop rotation will begin after the announcement of the strategic review,” said Jacek Siewiera, who served as the head of Poland’s National Security Bureau between 2022 and 2025. “The rotational U.S. presence has made an important contribution to Poland’s security. Our concern is the lack of permanence—given the changed security environment, this presence should now evolve into permanent basing,” Siewiera said.

The Polish official said that discussions on the permanent presence have involved several visits between the two sides, and they expressed optimism that the deal would move forward. “From what we know, we are on the right path to have this decision made,” the official said. Trump has been publicly supportive of the plans.

The former Polish diplomat was more skeptical, saying that “it might be much more realistic if there are clear decisions or public signaling” from Trump, the national security advisor, and the National Security Council. So far, the diplomat added, “these are lacking, just tweets or loose comments.”

For Warsaw, though, there may be little choice but to hope for the best. While European nations are rapidly rearming, none can provide the military capabilities of the United States. Russia’s escalating campaign of sabotage against Europe over its support for Ukraine, meanwhile, makes U.S. military commitments more important than ever—even if the Trump administration has shown increasing willingness to hand Russia economic wins and pressure Ukraine as the White House seeks to negotiate an end to the war.