World

U.S. military strikes on Iran would shake the regime's political control and damage its ability to launch counterstrikes, but the Iranians probably would manage to retaliate, directly and through surrogates, in ways that risked igniting all-out war in the Middle East, according to an assessment of an attack's costs and benefits.

The assessment said extended U.S. strikes could destroy Iran's most important nuclear facilities and damage its military forces but would only delay, not stop, the Islamic republic's pursuit of a nuclear bomb.

"You can't kill intellectual power," said retired Army Lt. Gen. Frank Kearney, who endorsed the report. He is a former deputy director at the National Counterterrorism Center and former deputy commander of U.S. Special Operations Command.

The report compiled by former government officials, national security experts and retired military officers is to be publicly released Thursday. It says achieving more than a temporary setback in Iran's nuclear program would require a military operation, including a land occupation, more taxing than the Iraq and Afghanistan wars combined.

An advance copy of the report was provided to The Associated Press.

The assessment emerges against the backdrop of escalating tensions between Israel and the U.S. over when a military strike on Iran might be required. The Israelis worry that Iran is moving more quickly toward a nuclear capability than the United States believes. The U.S. has not ruled out attacking but has sought to persuade Israel to give diplomacy more time.

Israel views a nuclear-armed Iran as a mortal threat, citing Iran's persistent calls for the destruction of the Jewish state, its development of missiles capable of striking Israel and Iranian support for Arab militant groups.

Tehran insists its nuclear program is for peaceful purposes only.