F-35: Will allies abandon F-35?

The simple answer is "probably not".  The reasons are multiple, but basically, the primary reasons have to do with the desire to have the best technology and capabilities available for their fighter pilots coupled with the understanding of the need for interoperability.  Only one fighter gives them those options.

Perhaps the "ground truth" of what will happen is best captured in an interview Australian Minister of Defense Stephen Smith recently gave.  In it he commits to the F-35:

We have committed ourselves contractually to two Joint Strike Fighters. We’ll receive those in 2014 in the United States for training purposes. We’ve announced that we will take another 12, effectively our first squadron, but we have not made a judgment as to when we will place the orders for those.

However:

I’ve made it clear since the time I’ve become Defence Minister that we won’t allow delays in the Joint Strike Fighter project to leave us with a gap in capability and at the end of last year, we placed a letter of request with the United States authorities to enable us to investigate the potential purchase of up to 24 more Super Hornets.

So, in the near future you're likely to see mixed fleets of 4th and 5th generation fighters.  As Thomas Donnelly and Phillip Lohaus pointed out in their recent AEI paper that we covered here:

The F-35 fleet is critical to ensuring that US forces and coalition forces are sufficiently capable at all echelons. It is crucial to understand the F-35 not simply as a uniquely capable platform, but as one of the few, if not the only, sources of operational mass in the Western Pacific theater. Without the mass and flexibility it provides, any first strike by China will fall on an inherently brittle defense. 

And, in fact, the F-35 will make 4th generation fighters more effective as well.  Australia obviously understands that.

The bottom line seems to be that perhaps the F-35's deployment among allied countries may be slower than first envisioned - some of that having to do with fiscal problems as well - but that it will still be the premier fighter jet among our allied nations. It simply offers too many advanced capabilities for the money to pass up. 

However you can expect to see that slowed deployment generate sales in 4th generation plus aircraft to fill the near-term gap.  At the point that the F-35's development reaches combat readiness and the price point stabilizes, you can then expect to see F-35's exclusively bought by these countries as they retire their 4th generation fleet.

Graff