Where's the exit? For Trump, harder to get out of the Iran war than into it

A hard truth for presidents: It's easier to get into a war than to get out of it.

Just ask Harry Truman about Korea, Lyndon Johnson about Vietnam, George W. Bush about Iraq.

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And now Donald Trump about Iran.

When Trump announced in a social media video Feb. 28 that the United States and Israel were striking Iran, he vowed that their overwhelming military advantage would crush the Islamic republic's navy, its missile capabilities and its nuclear potential − perhaps even overturn the government itself − in a war he suggested might last four to five weeks.

Now on week three, the United States has destroyed much of Iran's armed forces and its stores of missiles.

Its supreme leader, Ayatollah Ali Khamenei, has been killed.

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But the ayatollah's son has taken his place, and Tehran has managed to essentially paralyze the crucial Strait of Hormuz with the threat of mines and attacks from small boats.

That has spiked the cost of energy around the world and across the United States, including at the gas pump.

For Trump, that has made it both problematic to declare victory and increasingly costly to continue the fight.

"I think the president, frankly, is stuck," State Department veteran Aaron David Miller said on MSNOW.

All his options have downsides.

Asking allies for help – and hearing 'no'

"I think the president, frankly, is stuck," State Department veteran Aaron David Miller said on MSNOW.

All his options have downsides.

USA TODAY

Asking allies for help – and hearing 'no'

In a Quinnipiac Poll March 6-8, 53% of voters opposed the U.S. strikes, and 3 of 4 (74%) were against sending ground troops.

Nearly two-thirds (62%) said the White House hadn't provided a clear explanation for the military action.

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The survey of 1,002 registered voters had a margin of error of plus or minus 3.8 percentage points.

Only 1 in 5 predicted the war would last just days or weeks. More than 7 in 10 predicted it would last months or a year or even longer.

What defines a presidency?

Another lesson of history: Big wars tend to take over presidencies.

LBJ is remembered more for the misadventure in Vietnam than he is for the Great Society legislation that created Medicare and Medicaid.

George W. Bush's presidency is defined by two of America's longest wars, in Iraq and Afghanistan, which lasted longer than his tenure in office.

During his second term, Trump has been focused on his legacy − in adding his name to the U.S. Institute of Peace and the Kennedy Center, in campaigning for the Nobel Peace Prize with an argument he had settled wars from Armenia to Rwanda.

In Iran, though, peace now seems far away.