The USA will not choose between Pakistan and India at this time. We want to be friends with both without aiding and abetting a conflict between them. Only if either throws their lot in with the real enemies of the USA would the USA choose. That is the danger for Pakistan if it decides to openly and actually ally itself with the jihadis. In that circumstance, the USA might provide India with weapons that the USA knows or expects India might use against Pakistan.
does allying with china count as allying with a us enemy.
btw, the very notion of pakistan "openly" allying itself with tribal extremists is ridiculous