To be honest, this is all a Pak-US drama.
Maybe I'm floating a conspiracy theory but the sabre rattling seems to be a way of the PA trying gain credibility within Pakistan. Its a strange situation where if the PA comes out as friendly to US, it looses its legitimacy. A few rhetorical words here and there and a talk of war with the US is perfect to bring back your credibility and popularity ratings.
We now have Obama pretty much guaranteeing that there will be NO US boots on ground in NW. The PA/ISI will continue the game of catching a few Taliban and Al Qaeda members every now and then and over longer term, keep Afghanistan destablised and impoverished so that it never poses a challenge to Pakistan and it can focus only on the Indian border.
Until we see some concrete actions like sanctions or arms embargoes happening, the US-Pakistan relationship is still continuing.