The bombastic types are usually like this. They fold under pressure.
With a true narcissistic personality, they may back off but they are getting a plan together to rip right through anyone opposing them. Narcissist never see themselves as at fault thus they are—in their twisted mind—justified to destroy opposition even if they have to use others to do it and remain ‘above the fray’. Obama is a classic narcissistic personality and is proving his ‘back off’ routine is merely prep for ruthlessness.