Perparing for the nomination and the debates is more than appropriate. When he comes home, he'll be ready to face all the questions regarding his candidacy for the Presidency of the USA.
There is something wrong with being prepared? There is something wrong with being energized by allies and friends? There is something wrong with showing the electorate of the USA that he is not afraid of being welcomed by allies, while providing hope of a return of the USA all can trust?
He isn't campaigning for the Presidency in a way that states he is a candidate in the USA. I do believe Barak will be able to give speeches that sincerely reflect 'current' policies and tones of the relationships the USA shares with its allies.
The man knows what he is doing. After the nomination, he can have a campaign trail that leads to success, not guesses.
Go, Barak, Go !