Three weeks into Operation Epic Fury, the costs are impossible to ignore. Six American service members are dead. Oil trades above $115 a barrel. Qatar has declared force majeure on its LNG exports. The economy grew at 0.7 percent last quarter, and a recession is plausible within months. The Pentagon is requesting $200 billion in supplemental funding. Gas in California tops $5 a gallon.

The initial strikes against Iran's nuclear infrastructure were justified. Iran was weeks away from nuclear breakout, and 25 years of diplomacy had failed to prevent it. A nuclear-armed Iran would have triggered a regional arms race, made the Strait of Hormuz permanently unstable, and locked the United States into a posture of deterrence far more expensive than the campaign that destroyed the program. The decision to strike was correct.

But the decision to strike and the decision to wage a prolonged war are not the same thing. The American people did not sign up for a long war. The administration should not give them one.

The Length Is Everything

The difference between a successful military operation and a catastrophe is duration. Israel destroyed Iraq's Osirak reactor in 1981 in a single afternoon. The United States toppled the Taliban in weeks. Both achieved their primary objectives quickly and decisively.

The United States also invaded Iraq in 2003 with a three-week conventional campaign that succeeded brilliantly, followed by an eight-year occupation that cost 4,500 American lives, trillions of dollars, and ultimately achieved nothing that lasted. The initial operation was not the problem. The refusal to define an endpoint was.

Operation Epic Fury is now entering its fourth week. The nuclear facilities have been struck. Iran's air defenses have been dismantled. The conventional military has been degraded by 90 percent, according to the Pentagon's own assessments. The stated objectives of the campaign are largely accomplished.

So why are we still there?

Mission Creep Is the Danger

The administration's four stated objectives (destroy Iran's nuclear program, degrade its ballistic missile capability, neutralize its navy, and dismantle its proxy networks) were reasonable when announced. The first three are achievable through air power. The fourth is not, at least not through military force alone. Proxy networks are political organisms. They cannot be bombed out of existence. Attempting to do so is how three-week campaigns become three-year wars.

The deployment of A-10 Warthogs and Apache helicopters over Iran is a troubling indicator. These are close air support aircraft, designed to support ground forces in contested environments. Their deployment suggests either that the air campaign is shifting from strategic targets to tactical ones (which implies an expanding mission) or that ground operations are being contemplated. Neither possibility should comfort the American public.

The USS Boxer, carrying thousands of Marines, departed San Diego this week for the Persian Gulf. Marines are not deployed to maintain air campaigns. They are deployed when someone is planning to put boots on the ground. The administration should state clearly and publicly whether ground operations are being considered, and if so, it should explain why the campaign's objectives cannot be achieved without them.

What the American People Want

The American people will support a military operation that has clear objectives, achieves them, and concludes. They have demonstrated this repeatedly. They supported the Gulf War, which lasted six weeks. They initially supported the Afghanistan intervention, which achieved its stated objective (destroying al-Qaeda's base of operations) within months.

What the American people will not support, and should not be asked to support, is an open-ended military commitment with expanding objectives and no defined endpoint. They learned this lesson in Iraq and Afghanistan. The lesson cost 7,000 American lives and over $8 trillion. It should not need to be learned again.

The $200 billion supplemental request is a signal. When the Pentagon asks for four times its original estimate three weeks into an operation, it is planning for a long war, not a short one. Congress should demand answers before writing the check. How long? How many troops? What is the endstate? When do Americans come home?

The Realist Position

The center-right position on the Iran campaign is not complicated. Destroying Iran's nuclear program was a legitimate exercise of American military power in defense of American interests and global stability. A prolonged war of attrition against the remnants of Iran's military, its proxy networks, and its domestic political structure is not.

The United States does not need to occupy Iran. It does not need to change Iran's regime. It does not need to rebuild Iran's institutions or supervise its elections. It needs to destroy the nuclear program, establish deterrence against its reconstitution, and leave. Everything beyond that is a cost without a corresponding benefit.

The administration entered this conflict with the right instincts. It struck hard, it struck fast, and it achieved its primary objectives within days. The test now is whether it has the discipline to stop. The American people are watching, and their patience for prolonged military adventures was exhausted years ago.

The best wars are short wars. This one should be too.