"Every time a Tornado gets airborne, it passes through a point of no return on the runway after which, if there's a problem, there is no room to brake to a halt and the crew must eject and let the plane wreck itself"
That's a little unfair on the Tornado, almost every conventional jet aircraft, including the one that takes you on holiday, reaches a point of no-return, and the 747 doesn't have ejector seats!
It's simply a case of how much runway does the plane require to reach take off speed and then stop again. Most runways just aren't long enough for both.
Having said all that, I certainly won't defend the MOD's decision to scrap the Harrier and leave us with no Naval based air operations. You can can already see the effect that has had from the sabre rattling coming from Argentina. They wouldn't have dare do that again if the Harriers were still airborne.