18APR

Curtis becomes third Republican on AUMF

3 min read

14:57UTC

Utah's John Curtis was named on Saturday 25 April as the third Republican backer of Lisa Murkowski's draft Iran AUMF, which remains unfiled five days from the 1 May deadline.

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ConflictDeveloping

Key takeaway

Four Republicans on record against the war past 60 days, with no AUMF actually filed.

John Curtis, the Republican junior Senator for Utah, was named on Saturday 25 April as the third Republican backer of Lisa Murkowski's draft Iran AUMF, joining Susan Collins of Maine and Thom Tillis of North Carolina ¹. AUMF stands for Authorization for Use of Military Force, the legal instrument by which Congress authorises a President to use armed force; the last Iran-specific authorisation predates the current administration. Murkowski is the senior Republican Senator for Alaska and has drafted the text but not filed it.

Counting Rand Paul of Kentucky, who voted to advance the fifth War Powers Resolution on Wednesday 22 April when it failed 46-51 , four Republicans are now publicly willing to vote against The Administration's "winding down" framing. Cloture in the Senate requires 60 votes; a four-Republican bloc is well short of that floor but enough to embarrass The Administration on a procedural vote. Murkowski told Jewish Insider "we've been having some good conversations, and we're going to continue them" ².

The AUMF has not been formally introduced; there is no committee referral and no markup date. Five days separate today from the 1 May statutory War Powers deadline. If Murkowski had wanted floor action before that clock ran out, she would have moved the text by now. The most parsimonious reading is that the sponsor expects the deadline to pass without action and is positioning Republican senators for the post-deadline politics. The opposite reading is that the bloc is being assembled in case Trump signs an AUMF himself rather than face an unauthorised war past 1 May. Either reading requires signed paper to test, and there is none.

Deep Analysis

In plain English

An AUMF is a law Congress passes to formally authorise the President to use military force. The US has been at war with Iran for 57 days without Congress passing one. Senator Lisa Murkowski of Alaska has been drafting an AUMF, and three other Republican senators have now publicly said they support it. But she has not yet formally submitted the bill to Congress for a vote. This matters because until she files it, Senate leaders can't block it from reaching the floor, but it also cannot actually pass. The War Powers Act gives Congress 60 days to either authorise or end a military engagement; that clock runs out on 1 May.

Deep Analysis

Root Causes

Once **Murkowski** files the AUMF text, Senate leadership can route it to the Armed Services Committee and control the markup calendar, effectively bottling the bill indefinitely. An unfiled bill cannot be markup-blocked.

The five-day gap to the 1 May WPR deadline is therefore a deliberate strategic hold. Murkowski is accumulating public co-sponsors while preserving the option to file after the deadline passes, when the constitutional stakes are higher and Republican moderates face more pressure to commit to a position on an ongoing war that has no authorisation.

What could happen next?

Meaning
If Murkowski files the AUMF after 1 May, she converts the debate from 'war powers compliance' to 'congressional authorisation for an ongoing war', a more politically durable frame for Republican moderates to stand on.
Short term · Assessed
Meaning
Four Republicans willing to publicly oppose the administration's framing is the largest visible crack in Senate Republican unity on the Iran war, but it is still 56 votes short of cloture, meaning no floor action is possible without Democratic co-operation that has not been organised.
Short term · Assessed
Meaning
An AUMF that passes and contains geographic or temporal limits on the use of force would be the first signed executive constraint on the Iran war and would bind CENTCOM's rules of engagement in a way no Truth Social post can.
Short term · Assessed

Source Landscape

This story draws on centre-leaning sources from United States

United States

LeftRight

Primary parallel: The 1999 Kosovo intervention provides the closest procedural parallel. Congress passed a resolution authorising the deployment of ground troops that the Senate simultaneously defeated; the House then tied 213-213 on a resolution authorising the air war. President Clinton continued the 78-day NATO bombing campaign without any congressional authorisation passing.

The war ended, Congress never authorised it, and the War Powers Resolution question was never adjudicated. The 2026 situation is structurally similar: multiple WPR votes defeated, an AUMF drafted but not introduced, and a military operation continuing under executive authority alone.

Counter-parallel: The 2002 Iraq AUMF passed because Senators faced a midterm election six weeks after the vote and did not want to appear to oppose the Commander-in-Chief in wartime. The 2026 midterm cycle is 18 months away, removing the near-term electoral pressure that drove the 2002 coalition. Republican senators in 2026 can signal AUMF support without forcing the vote because the deadline cost is lower.

Consensus view: The Congressional Research Service has documented that the last time Congress passed a formal AUMF was the 2001 post-9/11 authorisation and the 2002 Iraq authorisation; all subsequent US military operations have been conducted under one of those two texts or under presidential war-powers authority. Georgetown Law School's Rosa Brooks, who has written extensively on the War Powers Resolution, notes that five WPR votes defeated in the Senate is itself a record for a single conflict inside 60 days, but each defeat preserves The Administration's position that Congress has not compelled withdrawal.

Counter-view: Heritage Foundation scholar James Carafano argues Murkowski's AUMF approach is constitutionally backwards: an AUMF authorises future military action rather than constraining current operations.

If Murkowski's goal is to require signed presidential authority for the existing naval blockade, a WPR resolution compelling withdrawal is the correct instrument, not an AUMF. The distinction matters because an AUMF vote that passes would actually expand presidential war authority rather than constrain it.

Key tension: Whether Murkowski's AUMF bloc is assembling leverage to force a White House concession on the terms of an authorisation, or is simply signalling disagreement without a viable legislative vehicle to compel any change.

First Reported In

Update #80 · Three carriers, zero instruments

Jewish Insider· 26 Apr 2026

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Causes and effects

Caused by

Collins, Tillis back Murkowski's Iran AUMF draft

Curtis joining the AUMF bloc builds on Collins and Tillis's public backing first reported on 25 April (ID:2780), taking the Republican bloc to three named senators.

Occurred 25 Apr 2026

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Senate rejects fifth WPR motion, 51-46

Murkowski's AUMF bloc assembly follows the Senate's rejection of the fifth WPR 51-46 (ID:2745), as Republican senators seek an alternative vehicle for the approaching 1 May deadline.

Occurred 22 Apr 2026

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This Event

Curtis becomes third Republican on AUMF

A signalling exercise rather than legislation: a fourth Republican name on a war they expect to outlast the deadline.

Led to

Murkowski misses her own AUMF deadline

Curtis adding his name as third Republican backer (ID:2813) still did not produce a bill number on Congress.gov by close of business 28 April

Occurred 28 Apr 2026

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Different Perspectives

Lloyd's of London war-risk underwriters

Lloyd's kept its Hormuz war-risk designation unchanged at $10-14 million per voyage even as Brent spiked 7%, holding the split from futures that has run since late May. Underwriters require a Security Council resolution or government certification, not a presidential phone call.

Gulf Cooperation Council states

Gulf states, having written to the IMO rejecting Iran's Hormuz transit authority, watched a fresh missile exchange land on Kuwaiti soil. Riyadh and Abu Dhabi remain caught between US security guarantees and Iranian fire, with no Gulf state co-belligerent except Kuwait.

China

Beijing stayed out of the diplomatic rupture, sending no envoy and offering no public position on the suspended talks. China keeps its bilateral energy corridor with Tehran while declining the exposure of a mediating role Trump barred it from anyway.

Kuwait

Kuwait's air defences engaged two Iranian ballistic missiles aimed at US forces late on 31 May, the second interception in days after invoking Article 51. Repeated strikes test whether Kuwait's politics can sustain hosting US forces as a de facto co-belligerent.

Lebanon and Hezbollah

Lebanon announced a partial ceasefire under which Hezbollah pledged to stop attacking Israel, the concrete output of Trump's call. Beirut heads to Washington on 3 June with Israeli forces still inside the south, testing whether the truce survives contact.

Israel under Netanyahu

Netanyahu stood down the planned Beirut operation under Trump's pressure but kept his ground advance running toward the Zaharani river, the deepest incursion in 25 years, and disputed Trump's claim that troops had turned around. Israel signalled the halt is tactical, not a wind-down.