Ron Futrell is confused there seems to be two different reactions by the same people to David Petraeus and has concluded there must be more than one:

Is this the same General Petraeus? I know that name from somewhere and I’m pretty sure it’s spelled the same.

Futrell goes on to list the differences between the two Petraeus’ and his confusion.

The answer seems to me quite simple. Petraeus is a time Lord.

His ability to turn spend so much time dealing with individual tribes obviously comes from being able to use his TARDIS to go back in time to learn all these customs and travel back and forth to have the time to get to all of these places.

As for the attitude change, that’s easy; he has obviously recently regenerated and like the Doctor’s daughter Jenny had one of those rare regenerations where his physical appearance doesn’t change.

The first sign of said regeneration was the collapse. He must have been at the beginning of his regeneration cycle

This would also explain the different take of the media, they without a question didn’t care for the 1st version of Petraeus but since regeneration changes personality then of course they are looking at him in a different light.

Now it simply remains to be seen if this new regeneration of David Petraeus is just as effective a soldier as the previous one.