Without wishing to sound omniscient, I (like others) said at the time that the success of CORPORATE would send an important message to the Warsaw Pact about British - and, to a degree, NATO - resolve. The seemingly ruthless sinking of the Belgrano, while a tragedy in human terms, would also have impressed the hard men of the Kremlin, in particular. Later that year I spent a few weeks with a (very hospitable) Bundeswehr armoured unit. Many of the officers and SNCOs were warm - indeed, almost effusive - in their praise of the operation, not least citing the enormous distances involved, the concomitant logistics, the Argentine numerical air superiority and, of course, the fighting qualities and tenacity displayed after the early naval and ground-force losses. Those views were, obviously, retrospective; I believe a US Navy assessment at the time of the deployment of the task force considered the retaking of the islands to be virtually impossible. It was certainly an important turning point in our post-Suez/Cold War history, and it is fascinating to speculate on what might have happened had Jim Callaghan (a wartime RN officer himself, of course) won the 1979 election and still been in No 10.
I seem to recall the Argentinians did try some sort build-up/stand-off when Callahan was in power, and naval forces were quietly dispatched, and the Argentinians backed off. Going back a long way, but I seem to recall there was some coverage in the Telegraph. I appear to be one of the few people who did know where the Falkland Islands were prior to 1982. Others may like to confirm this event under Labour in the late 1970s, and add to it?.
Despite critics, it must be remembered Callahan's Labour government gave us the Sea Harrier, the Chinook and the VC-10 tankers. The former two were instrumental in the Falklands conflict.