The review of the United States military presence in Europe remains an assessment process, not a final withdrawal decision. On September 18, 2026, the commander of U.S. European Command and NATO's Supreme Allied Commander Europe, General Alexus Grynkewich, joined a virtual briefing for Under Secretary of Defense for Policy Elbridge Colby on possible approaches to the review. Reuters reported that the Pentagon is preparing at least four sets of options for Defense Secretary Pete Hegseth while roughly 80,000 U.S. troops remain deployed in Europe.
What happened on September 18
The September 18 briefing was an internal step intended to help shape the alternatives that will reach Pentagon leadership. Grynkewich's role matters because he leads U.S. European Command, EUCOM, and also serves as Supreme Allied Commander Europe, SACEUR, connecting the U.S. national review with NATO military planning.
Reuters reported on September 18 that the process was still considering possibilities, with no final configuration announced. NATO had also confirmed in August that Colby briefed Allies on the ongoing review and linked it to the goal of increasing Europe's responsibility for collective defense.
What is under review
Documents described by Reuters show that the review is not limited to counting troops. It compares different ways to organize the U.S. military presence on the continent and to assess allied contributions.
| Area | What may be assessed |
|---|---|
| Force numbers and locations | Troop levels, the countries and facilities where forces are positioned, and possible redistribution within or outside Europe. |
| Pace and cost | The speed of any adjustment, related costs and effects on other U.S. global military priorities. |
| Access, basing and overflight | Conditions provided by Allies for base use, movement of forces and overflight rights. |
| Strategic infrastructure | Space, cyber, intelligence and other networks that support operations and power projection. |
| Allied capacity | Defense spending paths, fulfillment of NATO commitments and the ability to cover gaps in the NATO Force Model. |
On August 27, Reuters detailed the review's terms of reference. The document cited by the news agency calls for at least four sets of options and includes force levels, locations, speed of adjustment and costs among the criteria. It also considers access, basing and overflight, along with space, cyber and intelligence infrastructure.
Timeline and institutional actors
- June 2026: Hegseth announces a review of the U.S. military posture in Europe and says the process could last up to six months.
- August 27: Colby briefs NATO ambassadors on the ongoing review. NATO officially records the meeting and links it to rebalancing responsibilities within the Alliance.
- September 18: Grynkewich joins the briefing with Colby to discuss possible approaches.
- By November 6: the schedule cited by Reuters calls for at least four sets of options to be prepared for Hegseth.
- By December: the publicly stated deadline for completing the six-month review.
What limits Congress has already approved
The review does not take place without legal constraints. The Fiscal Year 2026 National Defense Authorization Act established guardrails for significant changes to the European posture. According to the summary published by Senator Jeanne Shaheen, the rule prevents the Pentagon from keeping troop levels in Europe below 76,000 for more than 45 days without the required certifications to Congress and consultation with NATO Allies.
The Congressional Research Service also notes that the law limits the use of Defense Department funds to reduce troop levels below that threshold, divest certain EUCOM sites and property, or relinquish the arrangement in which the EUCOM commander also serves as SACEUR unless the required certifications are provided. The 76,000 threshold therefore does not make a drawdown impossible, but it requires the executive branch to follow a process of justification, assessment and consultation before crossing that limit.
Confirmed vs. under review
| Confirmed | Under review or not yet decided |
|---|---|
| The review is underway and was announced in June. | The final number of U.S. troops in Europe. |
| Grynkewich joined the September 18 briefing. | Which countries, bases or units could gain or lose U.S. presence. |
| The Pentagon is preparing at least four sets of options. | Which option, if any, will be selected by Hegseth and the White House. |
| Roughly 80,000 U.S. troops are deployed in Europe. | Whether the review will produce further cuts, internal redistribution or retention of a substantial part of the current posture. |
| Congress created a procedural floor of 76,000 and other guardrails. | How any changes would be distributed geographically within Europe. |
What has not been decided
As of September 18, no final reduction tied to this review had been announced, and there was no official list of countries or bases that would lose forces. There was also no confirmation that troop levels would fall below the 76,000 threshold established by Congress. The existence of reduction options should be understood as part of the decision process, not as evidence that one has already been approved.
The review concerns U.S. force posture, conditions provided by Allies and the division of responsibilities within NATO. By itself, it is not a change to the North Atlantic Treaty or to formal collective defense obligations. The key point for following the issue without confusing options with decisions is to watch for the moment when the Pentagon turns the option sets into a formal choice and which consultations and certifications are triggered before changes that reach the limits set by Congress.
