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Consider this exchange on August 26 at the US State Department's daily press briefing. The department's spokesman, Ian Kelly, was fielding questions on the growing tensions between Iraq and Syria, following a co-ordinated series of bombings in Baghdad a week earlier that killed or injured several hundred people. The government of prime minister Nouri al Maliki accused Iraqi Baathists based in Syria of being behind the attacks, before recalling its ambassador in Damascus.

Asked about the Syrian-Iraqi dispute, Mr Kelly shuffled through his papers. “Yeah, if you could just hold on a second. We understand that there has been sort of mutual recall of the ambassadors. We consider that an internal matter. We're – we believe that, as a general principle, that diplomatic...