But the statement is a sign of growing concern in the US that the conflict in Syria is morphing into a complex regional war by proxy.

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Many Arab papers see the superpower confrontation over Syria as the start of a new Cold War by proxy, although one commentator says the Russian and Chinese positions could change.

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Left and right rarely meet in combat, preferring to fight their war by proxy: only 5% of their victims, it is reckoned, actually die with a gun in their hands.

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It's a war by proxy.

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This is war by proxy.

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They had been at war directly or by proxy for more than a decade, and were under increasing pressure from the international mediators and donors to stop.

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Some Central Asian states, such as Uzbekistan and Tajikistan, have joined Afghanistan's proxy war by backing the Uzbek and Tajik factions.

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Microsoft certainly knows a thing or two about anti-trust suits, and if the kids at Google are to be believed the company is waging something of a proxy war on them by injecting itself in lawsuits and complaints brought up by third parties.

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The danger is that each time they clash, even by proxy, they risk turning strategy into war.

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And that's what Ambassador Rice was talking about, and Secretary Clinton and I, because the consequences of not taking that firm action are more violence -- violence that spills over Syria's borders, violence that results in even greater participation in this by Iran, for example, and others, to the point where it becomes a proxy war of sorts.

WHITEHOUSE: Press Briefing