It is true that many of the people supporting Mr. Corbyn have never known what it was like in the 1970s; indeed, many of them have known little other than the Major-Blair-Brown-Cameron years which all roll into one. A lot of them are sick to the back teeth of austerity, and would not want to see the likes of the other candidates running the party.
So I think that he is likely to be elected party leader and, as has been pointed out, with the backing of the unions behind him many MPs will think twice before attempting a coup. Many of those MPs have been elected because of union backing as well, which they will be reminded of. I also think that a left wing Labour party will be much more attractive to many of those who have left in the New Labour years because of the move towards the centre-left, and they can command a lot of support as well. And as for those saying they would not serve in a Corbyn cabinet... crap. Of course they will.
PMQs could be interesting if Corbyn wins the leadership, as he is no Milliband and is less likely to be intimidated by Cameron. I think there will be less bluster and less opportunity for Cameron to score cheap points.
As for a Corbyn government... well, I wouldn't go that far yet, but I don't think it will be such a walkover for the Conservatives as everyone is saying. In any case, who knows what the political landscape will be in 2020. Cameron will not be fighting the election as party leader, and we could have Osborne as PM instead (dear Lord, really?).
But the question is, what will the armed forces look like under a Corbyn government?
Well, we already know that Trident is out, and there will be no expeditionary forces and no NATO commitments. Probably no UN commitments either. So as far as the Royal Navy is concerned, no carriers, no SSBNs and probably no Type 23 replacement. Type 45s and Astutes will stay, but reduced in numbers, with an increased emphasis on home waters. Bulwark and Albion might stay, Ocean out. No F-35 for the FAA, and a big reduction in helicopter numbers. Marines to stay, but vastly reduced in numbers and SBS absorbed into SAS.
The Army will lose a lot of capability, and will become essentially a home defence force comprising of mechanised infantry with artillery. Complete withdrawal from Germany, Falklands and probably all overseas bases, no attack helicopters, no tanks and far less of everything else. SAS shrunk in size with
As for the RAF, no offensive capabilities, so no F-35s, and Typhoon reduced to a couple of squadrons at most (30-40 aircraft). No need for large transports, but Voyagers retained due to contractual obligations, and SHF reduced to proportional size for the army. E-3s out, RC-135s out, Sentinels probably out, no drones of any kind at all. Red Arrows disbanded, BBMF to private operators. RAF Regiment disbanded/taken over by the army, Fylingdales closed.
That is extreme, but with no NATO or UN roles and no expeditionary forces, what else do you need for home defence only?