(CNN) -- President Barack Obama's surprise decision to seek congressional approval for a strike in Syria was a gamble that will likely succeed and over time may be judged deft. But the way he got there has also raised troubling questions about his leadership in foreign affairs. History strongly favors congressional backing. Over the past two centuries, presidents have asked Congress to approve the use of force before a coordinated military engagement on 18 occasions. Every time, the answer has been at least a qualified yes. The current Congress, of course, is also one of the most partisan and rambunctious of the past century, so there is a risk they will turn him down. But in the end, a majority -- especially in the Senate -- are likely to follow the example of Sen. John McCain. Despite his disagreements with the proposed strike (a "pinprick" to him), the Arizona Republican has concluded that it would be catastrophic for the country to strip the president of his authority and prestige as commander in chief. That argument -- along with others about the risks of emboldening Syria and Iran, appearing to leave Israel exposed and failing to act in the face of such horrific crimes -- will surely carry weight.
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Gergen, Zuckerman: Obama asking Congress' OK on Syria, a gamble that will likely succeed
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But they say the move follows an uneven strategy on Syria that has hurt his support
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They say it also realigns Obama with his own position before the invasion of Iraq
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Writers: U.S. needs long-term strategy on Middle East to show world it has firm grip
At home and abroad, observers watch carefully and calibrate their own responses by whether they think the @placeholder commander in chief and his team have a firm hand on the tiller.