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* However in certain limited applications we already have AI. The google search engine for example

The classic mistake of re-branding data-processing as AI.

* Getting a flying car that a non-pilot can fly and not crash into the myriad other flying cars is hard.

And land. Let's not forget landing. Any idiot can take off and fly and largely be successful at avoiding other things in the air. But getting safely back on the ground again? That's the REALLY hard part.

Almost as hard as building a personal vehicle with sufficient energy store and efficient propulsion to have a range that makes it useful for anything beyond saying "See! We built one!".

* Expect military applications [for driverless cars] in the next few years

But don't hold your breath for the broad and tumultuous changes to infrastructure and legal liability laws required to make widespread, meaningful personal use feasible.

* [cure] To all cancers, no. To some cancers, yes

Yes, the problem here is the categorisation of many disparate conditions with a common underlying cause into one "curable" thing. One might just as well posit a "cure for viruses". A cure for cancer is a null proposition.

* the problems [with developing fusion power] are engineering and material science not physics

That's true of any new technology. There was nothing stopping Neanderthal's from developing fusion power. The physics was the same, the lack of engineering and material science was the only problem. So sure, we can have anything (subject to the laws of physics being observed) we just need something unspecified and currently unknown and possibly unknowable to make it possible. You might extrapolate from this that it is only a question of time, possibly. But to put a timeBOX on that discovery, is to attempt to draw a long bow where the bow string is not fixed at one end - try it.

:)