The great Chas Freeman is saying this new alliance is 'primarily' to check Israel's expansionism and no need to be invoked into action until Israel tries something. I greatly admire Mr. Freeman's words.
Also, looking at the muted reaction from Washington, it seems like the alliance either has Washington's blessings or Washington is unable to do anything about it--the ongoing war on Iran has exposed the limits of America's power. Too much on hand to deal with. I also think the broad contours of Middle Eastern alignments were discussed when FM Asim Munir had the extended 'private lunch' with Trump about a year ago. But just because this might have America's blessings doesn't mean the alliance is America's puppet: I don't think it is the American policy to allow Israel to extend beyond its borders despite the importance given to Israel in America.