Thank you for the different perspective.
My historical reading had been similar to Hauritz; cut backs under the Nott report, and especially the withdrawal of the local patrol ship, emboldened the Argentinians to have a go, assuming Britain would be unable to respond. I think that may have come both from reading at the time and from "The Oxford Illustrated History of the Royal Navy"
Nice to see it from a more holistic point of view
The FO diplomats in South America were concerned but more credence was given by the Intel from the CIA through to the JIC. The CIA relationship with the Argies had two goals – the Argies continuing assistance to them via influence in a number of Central American issues and keeping them firmly within the DC orbit and a local counter to Brazil who were seeking a nuke capability and getting involved in middle east politics.
Viola the President from 1980 until December 1981 was the reformer within the Junta who put greater stock into economic changes than the simmering nationalism over the Falklands issue in which he was advocating a go slow with negotiations with Lord Carrington. Viola was also receptive to a Soviets offer of an economic package – his thinking an economic shot in the arm would stabilise the Junta more than appealing than the nationalist approach of taking the Falklands to consolidate popular domestic support. His Junta rivals arch anti communists Anaya and Galtieri were active in support of the CIA’s efforts in Nicaragua and both regarded Viola as weak (his health was failing at the time), they were the main protagonists of a renewed assertive position on the Falklands and made their move.
Even post December 1981 there was a view that due to the US influence over Galtieri and Anaya, enunciated by Argy FM Costa Mendes that though the rhetoric from Buenos Aires would involve sabre rattling an actual invasion was not imminent and that the US would act as a restraining influence on them.
The US adopted a tactic of diplomatic flattery towards Buenos Aires rather than “Don’t go there” with respect to Argy ambitions over a potential invasion. The Argies miscalculated this flattery. The British also miscalculated that by providing US access to Ascension Island that would be enough of a security guarantee in light of their planned reduced presence of UK assets in the South Atlantic.
What was going on in Whitehall at the time is cogently outlined in this paper by Japanese MOD defence academic Kenichiro Kotani.
http://www.nids.mod.go.jp/english/event/forum/pdf/2013/09.pdf
It will clear up some confusion and place into context about events as they played out amongst players within Whitehall in the timeline prior to April 1982.