If Britain had been in a better position in the 1980s - let's say they integrated former colonies a la France (not the Falklands though), the Suez Crisis didn't happen and through a myriad of events had a better economy. Basically, they aren't really US-USSR powerful, but still the worlds greatest Great Power - less of a "sleeping giant", but more of an active one.
Under that scenario, would Argentina still invade? Was the Junta dead set on an invasion no matter what?
I'd hate to be they guy bringing in the butterfly effect... bah, who I'm I kidding, I don't hate it at all. But let's go with the OP:
The UK remains a great power, likely the undisputed 3rd in the world. Argentina, a long term friendly/near colony of the UK, has the military choosing to have British advisers instead of French and American ones. A whole different set of juntas, coups or no coup at all means Galtieri doesn't become president.
Doesn't need any of this. Just a change to the defence review which indicates that HMS Endurance will be replaced would indicate to the Junta that we are serious about the area and put them off. However they were in deep trouble by 1982 so it was either the Falklands or Chile!
Furthermore if the Royal Navy of 1982 ITTL was the same size as it was in 1965 or even the 1950s IOTL then the British are going to have a stronger naval presence in the South Atlantic.
In addition to the ice patrol ship (probably the projected Terra Nova instead of Endurance) there would be between one and four frigates permanently based in the South Atlantic. Plus ships in transit between the Western and Eastern Fleets (if the Mediterranean Fleet was still merged with the Home Fleet in 1967). Therefore if the Argentine Government doesn't plan it properly a British aircraft carrier or guided missile cruiser might be in the South Atlantic on its way to Singapore or coming back.
And the British would still have use of the Simonstown naval base in South Africa. Either the Simonstown Agreement was still in force or the base might still belong to the Royal Navy.
So if the Galtieri is president and he needs a short war to keep him in power then it is going to be against Chile.
However, if the Falklands War still happens the Argentine armed forces are likely to have a greater proportion of British equipment. Their navy is likely to have Vickers built submarines instead of the American and German ones it had in the real world. In addition to the Type 42 destroyers, will be joined by British built frigates and corvettes instead of the French and German ones it had in the real world. There is a good chance that in addition to the Canberras in the Argentine air force would have a Mach 2 development of the Hunter or the Fairey Delta 2 in place of the Mirage IIIs and Daggers.
That would be embarrassing politically. However, could it have military advantages because the British commanders would know what the Argentine's equipment was capable of.
