(CNN) -- Iraq is suddenly back at the top of the news. The drawdown of "combat" troops has been completed, the handover to the State Department looks shaky, violence is ticking up and there is still no new Iraqi government, more than five months after the March elections. All these are real, but they are only the most immediate manifestations of deeper and longer term issues that the United States will need to manage. Our diplomats face big challenges. Let's start with the Iraqi government. Superficially, it looks as if former prime minister Ayad Allawi and present prime minister Nouri al-Maliki -- who came in first and second in the elections -- are in a huge personality clash. Why can't one of them be a statesman and step aside? The answer is that both they and other Iraqi politicians are worried about whether this will be their last opportunity to gain power.
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As U.S. combat troops leave Iraq, diplomats face challenge of building peace, says Daniel Serwer
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He says U.S. needs to guarantee the solution Iraqis develop to their political impasse
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He says spending on diplomacy protects $700 billion investment U.S. has made in new regime
The @placeholder needs to focus on finding ways to guarantee whatever solution the Iraqis work out.