For British Prime Minister David Cameron, it's not enough to act as a "moral humanitarian nation taking people, spending money on aid and helping in refugee camps."

"Assad has to go, ISIL has to go. Some of that will require not just spending money, not just aid, not just diplomacy but it will on occasion require hard military force," Cameron said, using an alternative acronym for "Islamic State."

Australian Prime Minister Tony Abbott has already announced plans for his country to join the US-led air campaign in Syria and he has not even ruled out the possibility of sending ground troops. France is already flying reconnaissance missions over Syria to gather information for potential air strike targets as President Francois Hollande announced his intention to join the US-led campaign in Syria on Monday.

'Bombing people to save them'

But air strikes aimed at protecting civilians are rarely effective, according to Taylor Seybolt. Air strikes have a chance of success only at the start of a conflict - before the warring sides are entrenched - or at the end when they are exhausted. The strikes also have to defend a focused area for a limited amount of time, Seybolt told DW. None of these conditions are currently present in Syria.

Over 250,000 have been killed in the Syrian civil war

"Bombing people to save them isn't really a good practice," said Seybolt, the author of "Humanitarian Military Intervention: The Conditions for Success or Failure."

"The talk about humanitarian bombing is not focused on a particular safe area or population," Seybolt said. "It's just sort of a broad statement that we're going to try to help people so that they stay were they are rather than come across to Europe."

Safe zones risky

Turkey, which has become home to nearly 2 million Syrian refugees, has proposed safe zones on the Syrian-Turkish border in the past. But this strategy would require boots on the ground, according to Benjamin Valentino, who researches humanitarian interventions. He said the civil war in Bosnia during the 1990s provided a cautionary tale to today's leaders.

"Unless we're willing to defend those safe zones on the ground, those safe zones will be quite vulnerable," Valentino, with Dartmouth University, told DW. "What will happen is more likely to be what happened to the safe zones in Bosnia. They were eventually overrun because they weren't adequately protected on the ground."

There's no stomach in the West for sending in ground troops, and there are few reliable, organized groups to work with in Syria, Valentino said. Without soldiers on the ground, discriminating between the victims and the perpetrators will be difficult.

"It's very difficult to actually protect civilians on the ground using airplanes that are flying at 500 miles an hour and at 30,000 feet," Valentino said. "Even drones are just not good enough to spot all the perpetrators, separate them from the victims and target them."

Russia complicates solution

Islamic State is only the "by-product" of the larger Syrian conflict, according to Majid Rafizadeh. Right now, "the West are targeting and attacking the symptoms rather than the disease."

"The underlying root of the problem is the ongoing Syrian conflict," Rafizadeh, an expert on Iran and Syria at Harvard University, told DW. "There is a need for a more comprehensive strategy. The West should look at the root of the issue and put aside the 'wait and see' policy towards Syria and ISIS."

Syria's civil war has been raging for over four years

Finding a comprehensive political solution to the conflict has been complicated by reports of direct Russian intervention in support the Assad regime. According Seybolt, third party intervention often prolongs a conflict, complicating its resolution.

"It very disturbing that Russia is sending more material support to the Assad regime," said Seybolt, who is also with the Ford Institute for Human Security. "That will really get in the way of any sort of diplomatic initiative by the UN or any third party that's capable of being a mediator in negotiations."

"You pour soldiers and weaponry into an ongoing conflict and it's likely to get worse before it gets better," Seybolt added.

Accepting refugees helps more than air strikes

With the prospect of a political solution remote, the best way to help the people of Syria at the moment is to shelter those who manage to escape the conflict, according to Valentino.

"Many countries in the West are not interested in doing that, but I think that's more likely to help people than dropping a few bombs in Syria," he said.

While Germany will welcome more than 800,000 refugees this year, Britain has agreed to shelter just 20,000 people over the next five years. France will take in 24,000 in 2015. Distant Australia has agreed to 12,000 this year. The United States on Thursday announced plans to accept 10,000 refugees over the next year. There are reports that Washington will increase the cap on its refugee quota from 70,000 to 75,000.

The Syrian civil war, which started over four years ago, has killed more than 250,000 people and driven more than 4 million from their homes, according to the United Nations.

Under the international law, refugees are required to apply for asylum in the first safe country they enter. Geographically, countries like the United States and Great Britain are more distant from the conflict zone than Germany or other European countries on the front line of the current refugee influx. But this shouldn't let them off the hook, he said.

"Because the UK and the US aren't the countries of first entry, they're doing what they're legally obligated to do," Seybolt said. "On the other hand, there's a capacity to accept far more refugees than those countries are accepting, and that capacity should be used."

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