When Mr Bush recently dared mention Mr Nour, Egyptian officials riposted with a blistering demand that he mind his own business.

ECONOMIST: Democracy in Egypt has stalled

Not so fast, riposted Mr. Carney, who changed his Twitter alias to Justin Bieber, replacing his own photo with one vaguely resembling his newfound enemy.

WSJ: Moving Targets: Queenan Imagines Twitter Feuds Involving Burr, Capone