Secretary of State John Kerry says the White House is planning an “unbelievably small” strike against Syria’s regime to punish it for using chemical weapons against civilians in Damascus.

That’s contrary to other reports from the Pentagon, where officers are reportedly planning a two or three-day campaign, complete with hundreds of strikes from ships and long-range bombers.

“We will be able to hold Bashar Assad accountable without engaging in troops on the ground or any other prolonged effort — in a very limited, very targeted, very short-term effort, that degrades his capacity to deliver chemical weapons,” he told an audience in London.

“What we’re talking about doing [is] an unbelievably small, limited kind of effort,” he said, similar to previous strikes “on many different occasions.”

Those occasions likely include a small strike against a factory in Sudan, or the four-day Operation Desert Fox attack on Iraqi sites. Both 1998 attacks were conducted by President Bill Clinton.

Kerry is clearly hoping the promise of a small strike will help persuade a reluctant public to support the military intervention.

The uncertainty over the White House’s plans complicate the political problem facing Senate and House legislators, who are being pressed by President Barack Obama to authorize some kind of punishment against Syria.

White House officials say the punishment will be large enough to deter future use of chemical weapons by dictators, but not large enough to help the various jihadi rebel groups — including al-Qaeda affiliates — defeat the government and seize the country’s large stockpile of nerve-gases.

But without a confirmed attack plan, officials are describing a variety of proposed attack plans. That confusion makes it difficult for legislators to judge whether any plan will do more harm than good, or might even draw the United States deeper into Syria’s complex, sectarian, tribal and cross-border civil war.

ABC News has reported that the operation is expected to inflict “more damage to Assad’s forces in 48 hours than the Syrian rebels have done in nearly two years of civil war.”

The plan, says ABC, includes strikes by 200 ship-launched Tomahawk missiles, plus a rain of bombs and missiles from B-52 and stealthy B-2 bombers.

The Los Angeles Times reported that Pentagon officials were planning a three-day barrage. “There will be several volleys and an assessment after each volley, but all within 72 hours and a clear indication when we are done,” said one officer, according to the Times.

But the three-day strike “will not strategically impact the current situation in the war, which the Syrians have well in hand, though fighting could go on for another two years,” said another U.S. officer cited by the L.A. Times.

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