Through two years of Syrian crisis, the Obama administration has cautiously dragged its feet as the United States is further enmeshed in the conflict. That's a sensible platform at home, with opinion polls showing that Americans don't think the country has a responsibility to intervene.

It has strategic merit, too, given that intervention against Bashar al-Assad is an implicit endorsement of a largely unknown opposition force with radical, sectarian factions.

But the status quo in Syria is breaking down, and Obama's worst option is to kick the can as the United States inexorably gets dragged deeper into the conflict. It may be politically painful, but it's time to make a choice: Go all in with a no fly zone - or avoid anything more than diplomatic intervention and humanitarian/non-lethal aid. Here's why.

Until recently, Obama's strategy of hesitance and risk aversion was commendable and well executed. As the situation worsened, the US took minimal, reactionary steps. First, then-Secretary of State Hillary Clinton tried to put together a formal - and reasonably liberal - Syrian political opposition, but it quickly fragmented because it had no workable ties to the actual rebels doing the actual fighting.

Then the US turned to non-lethal aid for the rebels (including defensive military equipment) as well as supporting Qatar and other countries through intelligence and logistics. Furthermore, in August 2012, Obama drew a "red line" at "chemical weapons moving around or being utilized" by the regime. At the time, it seemed unlikely to come to fruition anytime soon.

A lot has changed in the past few weeks, which have been the most turbulent since the crisis began two years ago. Reports that Assad may have deployed chemical weapons have become too loud to ignore (along with conflicting assertions that the rebels may also have done so).
The violence is intensifying, with reports of civilian slaughters at the hands of the government. Israel conducted two direct military strikes against Iranian missile supplies on Syrian soil. The refugee crisis continues to deteriorate, with more than a million people occupying ramshackle camps in Jordan, Lebanon, Turkey and Iraq. Meanwhile, Assad is consolidating his military advantage.

Ugly as the situation was, it's now much uglier - and faster-moving.

And so it appears the US is slipping deeper into the fray. This week, Defense Secretary Chuck Hagel became the first senior official in the administration to say "arming the rebels - that's an option."

Senator Robert Menendez (D-N.J.), the chairman of the Senate Foreign Relations Committee, introduced legislation that would provide weapons to the Syrian opposition. The committee's ranking member, Bob Corker, said, "I think that we will be arming the opposition shortly. We are doing a lot more there on the ground than really is known."

All of this means the calculus is no longer what it was a year ago, or even six months ago, but Obama is using the same reluctant tactics of minimal engagement.

As it became clear that Assad may have crossed his "red line," Obama simply redrew it, saying the "systematic use" of chemical weapons was the new line in the sand. But the current policy is a one-way street. The United States is only becoming more deeply involved, arming rebels who may or may not be better stewards of a country riven with sectarian conflict.

Offering arms to the rebels doesn't solve Syria's problems. It certainly doesn't decrease the bloodshed. In the near term, it will almost assuredly do the opposite and it is bad policy for the United States, for two reasons.

First, the United States would be arming a largely unknown opposition force, and once it offers military aid, it will increasingly be attached to the rebels, and to any atrocities they commit before or after toppling Assad. Ultimately, if the rebels are able to defeat Assad, the war's legacy will leave sectarian warlords grappling for power, keeping the country violent and volatile going forward.

Second, what if the rebels lose? In the past few weeks, Assad has been consolidating his military position and regaining the edge in the civil war. The Iranians have been arming the regime. A rebel victory will thus be bloodier and more unlikely.

Once the United States arms the rebels, it's an implicit backstop. Should the rebels require a no-fly zone down the road, the US would feel political pressure to provide it. The United States would have to assume whatever cost is necessary to keep the rebels afloat.

So what should the United States do? It should recognize where things are heading and take decisive action, one way or the other, as soon as possible. Delays and incremental steps toward military intervention cost lives and undermine the eventual strategy that the United States chooses to pursue. It's time to pull back or dive in.

The first option is difficult to navigate politically but has its merits. Obama could announce that the US will not take sides in the war. America won't support the rebels, just like it won't support Assad, and it will focus on humanitarian and diplomatic efforts.

Obama could assert that while a humanitarian crisis that has resulted in more than 70,000 deaths is atrocious, the United States does not have the resources, authority or direct security interests necessary to take sides or engage militarily to keep the peace.

The United States would essentially take a backseat and glue itself to the chair - a "risk repulsion" strategy as opposed to the risk aversion that Obama has been practicing. But it would keep up diplomatic pressure, however ineffective it might prove to be.

That means more initiatives like Secretary of State John Kerry's trip to Moscow. He has spent the week trying to persuade Russian officials to convene an international conference on Syria's future.

In Russia, the United States dropped its hard line on Assad, not stipulating to the Russians that Assad has to go. In return, the Russians have shied away from their platform that Assad has to stay.

The drawback to this strategy is that it will likely prove ineffectual, and the humanitarian disaster in Syria will worsen. But our current trajectory has the same two drawbacks - and this approach will keep America out of direct military engagement.

The second option is more violent, more expansive and more dangerous, but it's safer in the long term for Americans and can be more productive for Syrians. The United States could bomb Assad's anti-aircraft defenses to set up a no-fly zone over Syria.

Imposing the no-fly zone is going to take allies, just like it did in Libya. Obama will have to assemble a coalition of the willing, including partners such as Britain, France, Canada, Qatar and Saudi Arabia.

The pitch is simple: The no-fly zone will (hopefully) impede much of the violence that the regime's air force can inflict on the rebels. It would help create the conditions for a cease-fire once that imminent threat against the rebels is removed.

That, in turn, would allow for a massive humanitarian intervention, including military troops on the ground to separate the regime from the rebels. With some semblance of economic normalcy restored, the refugees can move back, localized governments can be established and the regional crisis can be limited even while Syria's crisis continues.

We are, of course, a long way from all of this working. A no-fly zone will likely anger the Russians, the Iraqis and the Iranians - though it's unclear how much Washington need care about the last. It'll also be expensive and put Americans in harm's way. It's incredibly messy, expensive and it's no panacea.

But it will allow America to dictate the terms in which it enters the fray - and not to take sides. It will mean bombing Assad's defenses, yes, but it will do it for humanitarian reasons, not, at least ostensibly, to help install the rebels.

You can make a case that attacking Assad's defenses is tantamount to supporting the rebels, but you could also claim that pushing for a cease-fire is tantamount to letting Assad remain in power. The no-fly zone is an attempt at neutralizing the damage that both sides can inflict on the other, while allowing governance and refugees to return to Syria.

Clearly, the reason the Syria decision is so difficult is because there's no right answer. There are only bad and worse choices. Today, the worst choice is unfortunately the most politically expedient: continuing with the current trajectory.

More people die in the interim, and when the United States wakes up to find itself mired in direct involvement, it will be too late to pull out - or to co-ordinate its military engagement in an optimal, predetermined manner. Its intervention will be piecemeal, inefficient and leave all parties worse off.

For the US, the Syrian crisis has come to an inflection point. This was not the case just six months ago, but it is apparent now. America has a hard choice to make: Say no to arming the rebels or yes to deeper military engagement. Unfortunately, inaction is the simplest path forward - and the worst one of all.-Reuters

(Ian Bremmer is a Reuters columnist. The opinions expressed are his own.)