Image caption If the US attacks, US policymakers have no idea whether Assad will step up the rhetoric and the violence

US officials hope that any military assault on Syria will be surgical and limited. But what does the US do after the missiles or bombs have fallen?

It could go either way. The US may attack - or may not. "I've not made a decision," US President Barack Obama said on Wednesday.

Mr Obama has maintained that if the Syrian government uses chemical weapons, the US will act militarily.

And last week, according to US officials, President Bashar al-Assad's forces deployed poison gas against rebels in a Damascus suburb. More than 1,000 people, including women and children, were reported killed.

Syrian government officials say they did not use chemical weapons, but the US is ready to act.

'We are prepared'

Image caption Operation Desert Fox in Iraq was "short" - similar to an operation planned in Syria

UN inspectors are looking for evidence of a gas attack in the Damascus suburb, and plan to finish their work on Friday.

Meanwhile officials in Washington DC are laying the groundwork for military operations.

"We are prepared," Defence Secretary Chuck Hagel told the BBC.

If US officials proceed with military operations, they will likely be supported by Turkey and France, at least in some fashion. They will not have the backing of the UK, where Parliament on Thursday night rejected a government motion supporting intervention in Syria.

Nor is the UN Security Council expected to support an attack, because the Russians are opposed.

The US military would most likely use Tomahawk cruise missiles for an attack on the Syrian government forces. These missiles are now stored on destroyers in the eastern Mediterranean.

The missiles would not be fired at places where chemical weapons might be stored, since poisonous gas could spread or chemical agents could fall into the wrong hands.

Instead, military facilities would be targeted - radio centres, command posts and missile launchers, says Douglas Ollivant, who served as an operations officer with the Army's Fifth Cavalry Regiment in Iraq.

The initial military operation would be fast.

Public opinion

Image caption Defence Secretary Chuck Hagel says the US is "prepared" for military action

"It would be a fairly short, sharp action - much like Operation Desert Fox," a 1998 military operation in Iraq, says Peter Mansoor, an Ohio State University professor of military history who served as executive officer for David Petraeus, a retired US Army general, in Iraq.

Mr Obama has been looking for a way to retaliate against the Assad regime for the chemical weapons. If he proceeds with a missile strike, he will follow a long line of US presidents who have tried to avoid bloody ground battles.

The missiles would likely be deployed from the sea, without putting Americans in danger.

This option is more palatable to the US public than the deployment of ground troops. Most Americans do not want the US to get involved in the Syria conflict, according to a Quinnipiac University poll.

Yet roughly half of the Americans polled said they were open to military action - if the operations were done from a distance.

They don't want to do something that could look like an empty gesture Suzanne Nossel, Former deputy assistant secretary of state

Indeed, remotely controlled attacks such as air strikes have been called "the American way of war" by the authors of an article in Foreign Affairs magazine.

Unfortunately, the notion of effective and pain-free distance warfare is illusory.

In March 2003, the US "shock and awe" bombing campaign in Iraq did not on its own bring down Saddam Hussein.

"It still required a ground force invasion," said Kalev Sepp, a former special forces officer who is now a senior lecturer at the US Naval Postgraduate School.

Besides that, bombs and missiles are only as effective as the intelligence targeting them.

In 1998, US cruise missiles destroyed a pharmaceutical factory in Sudan, because intelligence analysts had believed it to be a chemical weapons factory.

An earlier military strategy based on remotely controlled strikes, the Nato air war in Kosovo, has reportedly been discussed during high-level Obama administration meetings about Syria.

Not everything went smoothly during that bombing campaign, either - the US blew up the Chinese embassy.

"There's these mistakes - shortfalls - and they have counterproductive value," says Mr Sepp.

'You failed'

Mr Obama says that the objective of any military strike would simply be to warn the Assad regime not to use chemical weapons again.

"The Assad regime, which is involved in a civil war trying to protect itself, will have received a pretty strong signal," Mr Obama said.

What happens afterwards, though, is anybody's guess.

"They don't want to do something that could look like an empty gesture," says Suzanne Nossel, who served as a deputy assistant secretary of state during Obama's first term.

"They'll wait for a reaction. Does Assad step it up with the rhetoric - 'you failed in Iraq, you failed in Vietnam'? Or does he take the beating?"

If the Assad regime decides to ratchet things up, Mr Obama has an array of options - none of them good.

"The range is, you do nothing - all the way up to large-scale air and ground campaigns to remove the Assad regime," says Mr Sepp.

"You can send in special forces to train and organise the rebels. But it's impossible to do that clandestine. So then you have to have Americans on the ground - and they're being killed. Is that worth overthrowing the Assad regime for?"