# Elbridge Colby Elbridge Colby is Under Secretary of Defense for Policy — the Pentagon's third-ranking civilian and the official who writes strategy documents and runs force-posture reviews. He is the most consequential intellectual architect of the current administration's defence policy, and the person most responsible for the fact that its approach to alliances has a coherent theory behind it rather than only a set of grievances. He was principal author of the **2018 National Defense Strategy**, the document that formally reoriented American defence planning from counterterrorism to great-power competition. His 2021 book *The Strategy of Denial* argued the case that has since become policy. ## The Argument Colby's position is best understood as **prioritization rather than isolationism**, and getting that distinction right matters for reading anything he does. The claim: the United States lacks the military capacity to fight China, Russia, and Iran simultaneously. Its defence commitments therefore exceed its means, and the mismatch is not fixable by spending more at any politically plausible level. The only responsible response is to rank the theatres. **China and the Western Pacific rank first.** Europe ranks below, because European states are wealthy enough and populous enough to conventionally deter Russia themselves and have chosen not to. The Middle East ranks last. The policy implications follow directly: press European allies to take primary responsibility for their own conventional defence, shift American forces and munitions toward the Indo-Pacific, and treat allied burden-sharing as a hard requirement rather than an aspiration. This is not the same argument as "alliances are bad" or "retrenchment for its own sake." Colby is a China hawk who wants alliances to work harder. But the operational consequence — fewer American troops in Europe, less capacity available to European contingencies — is largely the same as the isolationist one, which is why he is claimed and attacked by both camps. ## What He Has Actually Run **The AUKUS review.** Colby launched it on 11 June 2025, alarming Canberra and London for six months. It concluded by 4 December 2025 with a **full endorsement**: the framework serves US interests, statutory authority is intact, transfers proceed. See [[AUKUS]]. This is the clearest evidence that his framework is not reflexively anti-alliance — AUKUS is Indo-Pacific and it survived. **The 2026 National Defense Strategy**, released 23 January 2026. Four priorities: homeland defence, deterring China, allied burden-sharing, and the defence industrial base. Its most-discussed feature was a sharp hemispheric turn that analysts described as a "Trump corollary to the Monroe Doctrine" — roughly 11,000 troops surged for Caribbean operations as of December 2025, permanent Caribbean footholds, expanded Greenland basing. On Europe, allies are expected to take primary responsibility for Russia with the US in a backup role, and are characterized in the document's framing as freeloading dependents. **The Europe force-posture review**, kicked off on **29 July 2026** and expected to take up to six months. Announced by [[Pete Hegseth]]; run by Colby. Its stated goal is moving NATO "toward Europe taking primary responsibility for its conventional defence." > [!warning] Outcome pending > **No troop reductions or base closures have been announced under this review**, and no global posture review document has been published. The May 2026 cuts — four Brigade Combat Teams to three, 5,000 troops out of Germany, a 4,000-troop Poland deployment delayed — preceded it. The review's conclusions land around January 2027. ## Why He Matters Here Colby is the answer to a question the vault's institutional pages keep raising: is there a theory behind this, or only a disposition? For the [[World Trade Organization]], the [[International Criminal Court]], the [[Organization of American States]], the answer is mostly disposition — a general hostility to external constraint, applied opportunistically. For defence policy there is an actual argument, published years in advance, internally consistent, and now being executed by its author from the office that executes it. That makes the security layer different from the rest of this cluster, and it changes what counts as a good critique. Objecting that the Europe review is anti-alliance misses the point; Colby would say the alliance is being made sustainable. The serious counterarguments are narrower and better: that European conventional rearmament takes a decade the [[Russo-Ukrainian War]] does not allow; that deterrence is a belief rather than an order of battle, so publicly ranking Europe second degrades it before a single soldier moves; and that the hemispheric turn in the 2026 NDS is not derivable from the prioritization argument at all and looks like a separate agenda riding along with it. The [[Coalition of the Willing]] is Europe's answer to Colby's premise — allies taking primary responsibility, exactly as instructed, and building a structure the United States does not control in the process. ## See Also - [[AUKUS]] — the review he ran and endorsed - [[NATO]] · [[NATO Summit Ankara 2026]] — the alliance under his posture review - [[Mark Rutte]] — managing the alliance through it - [[Coalition of the Willing]] — the European response to the premise - [[Quadrilateral Security Dialogue]] — the Indo-Pacific grouping that is drifting anyway - [[Pete Hegseth]] · [[JD Vance]]