09/10/2013 04:58 EDT | Updated 11/09/2013 05:12 EST

Obama's Syria Pitch: How Pivotal A Moment For The U.S.?

When U.S. President Barack Obama takes his case for a strike against Syria to the American people tonight, he will be making a pitch to a country where many are at best only lukewarm toward the thought of intervening in a civil war that has taken more than 100,000 lives.

On Monday, a poll by The Associated Press found that most Americans oppose even a limited attack on Syria. That response comes even though they’ve been told — repeatedly — by the administration that doing nothing, particularly in the face of apparent chemical weapons use, would risk national security and ignore a humanitarian crisis of immense proportions.

The current debate — which will officially make its way to the U.S. Congress later this week — brings with it questions over the extent to which a country where many seem weary with war intervenes or isolates itself from the world stage.

And it also leaves open the question of whether the Syrian crisis is another in a long line of pivotal moments for the largest military and economic power in the world.

"Is it a referendum on isolationism versus interventionism — yes it is, and that’s an ongoing conversation in America," says Peter Loewen, a political science professor and director of the Centre for the Study of the United States at the Munk School of Global Affairs at the University of Toronto.

"But the pendulum has swung more towards isolationism than ever in the last 15 years."

Loewen sees several factors playing into that swing: the U.S. experience and "lack of apparent success" in Afghanistan and Iraq, the fact that "Syria is a particularly messy case," and the nature of domestic politics at the moment.

'Tired of war'

"There’s a few things here," says Loewen.

"One is just a longer-term thing about being tired of war. The second is serious doubts about the possibility of success in the Syrian case and what would success mean. And the third case is a real animosity toward President Obama among a good number of Republicans and their voters."

But Loewen stops short of considering that the U.S. is at a hugely significant and pivotal point when it comes to its position on the world stage.

"I don't think this is a make-or-break moment. The United States remains the largest military power in the world, the largest economic power in the world, so the country can't be pushed from its throne with one event."

For Obama, however, Loewen sees considerably higher stakes.

"It's certainly a pivotal moment one should think in the presidency of Barack Obama,” because, suggests Leowen, “he risks not being able to back up his talk with action."

Other observers don’t see this week's Congressional vote as a referendum on isolationism versus interventionism to the same degree.

"The United States doesn’t really have the option of isolationism in its current phase," says Reva Bhalla, vice-president of global analysis for Stratfor, a Texas-based geopolitical intelligence firm.

"The U.S., relative to the rest of the world, still retains a lot of wealth, a lot of power. Now the challenge for the U.S. is learning how to preserve that power."

2 schools of thought

To do that, Bhalla suggests, there are two schools of thought.

"The more interventionist school of thought is that, 'Well, the U.S. has this power, therefore it must exert that influence abroad and apply it to humanitarian crises around the world, the global policeman sort of role.' "

The other school of thought, and one Bhalla says is gaining more popularity right now, grows out of the U.S. experience in places like Iraq, Afghanistan and Libya — and now Syria — "where there’s an argument that the United States needs to one, acknowledge its power, but also work to preserve that by recalibrating its priorities, being able to focus on what matters and not allowing itself to get bogged down in conflicts around the world."

The question gets asked again and again, whether actions in Syria threaten U.S. national strategic interests.

"I think that question is one that the United States has become much more aware of after its experiences in the Middle East and so it's more about the preservation of that power — and acknowledgment that isolationism is not an option — but tempering its interventionist policies at the same time."

Bhalla considers this a "very significant moment" for the United States, particularly as interest grows in a Russian proposal to contain chemical weapons in Syria.

That proposal emerged after an offhand remark on Monday by U.S. Secretary of State John Kerry and would require Syria to agree to place all it chemical weapons under international control for eventual destruction and sign the international treaty banning chemical weapons. That would avert an American military response.

"If the U.S. does try to back away from its position to militarily intervene in Syria, even if it’s a limited strike, then you're going to have countries around the world, allies of the United States, asking themselves what is a U.S. security guarantee actually worth," Bhalla argues.

For Obama, as a second-term president, the cost is not as high as it could be, he says.

'Lost a lot of credibility'

"His presidency has lost a lot of credibility in foreign policy with this whole episode over Syria, beginning with the red line statement and where we are now and Congress debating whether this actually addresses the U.S. fundamental interest and Obama having to answer to that."

If members of Congress start showing interest in the Russian proposal, as some Europeans are, Bhalla suggests it will be very difficult for Obama to move ahead with intervention in Syria. Obama himself said Monday in an interview with NBC News that the proposal "could potentially be a significant breakthrough," although he immediately expressed skepticism Syria would follow through.

"There's a very real chance that he may have to back down and that of course will have political repercussions in the U.S. and abroad."

In ways, the international focus that inevitably falls on the U.S. may, by default, define the Syrian debate as another in a long line of crucial moments for the country.

"If something happens in the international community when there is a security issue, everyone looks to the U.S., so it's always a pivotal moment, it's always a defining moment," says Lori Turnbull, an associate professor of political science at Dalhousie University in Halifax.

"And in that sense I guess their identity is always in play. It's never settled."

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