Try to stick as close to real-life history as possible, but what would be the most logical progression which could lead to the Argentine military deploying anti-satellite weaponry? Ground, sea, or air-based options are all on the table. Bonus points if you can make it happen before the Falkland Islands War.
EDIT: The POD can be any time between 1947 and 1982.
What you're asking for is highly implausible prior to the Falklands War without a really big butterfly
Almost no one IRL had anti-satellite capabilities by the Falklands War. The US and USSR didn't really do much with the concept until 1982, the year of the Falklands War itself. The USSR had a longer research program with at least one successful intercept by 1970, but amped up research in response to the US's declaration of an SDI program in 1982. The US didn't even get into the game until 1982 with the SDI and didn't have a working program until 1985. No other country has even tried interception technology until India and China in the last one and a half decades.
Basically, for years and even now anti-satellite technology has been the domain of superpowers. If only the two big superpowers (and arguably only one, the USSR) had the power to shoot down satellites by 1982, it's highly unlikely there is anything Argentina could do to get that technology within the time frame you ask (1947-1982).
The only possibilities I see are either:
Argentina goes communist and the Soviets lend them their technology, creating a situation akin to the Cuban missile crisis. But this is unlikely because the Soviets had personal motivation for putting nukes on Cuba.
Some massive butterfly effect happens and Argentina becomes a superpower. But this would require a divergence way outside your bounds, and would require something like Argentina conquering Chile, Bolivia, Paraguay, Uruguay, and maybe more to have the size and resources necessary to compete as a superpower with the US and USSR. However, this would completely screw up the Cold War (the whole reason the Cold War happened is you had only two competing superpowers, rather than a third that could break the stalemate) and Argentina would be almost unrecognizable culturally and politically. The Falklands War would probably turn into World War III in this scenario as an invasion of the territories of a NATO-member country by a rival superpower would provoke all out war between Argentina and the US/Europe, compared to OTL where other countries mostly provided support and very limited amounts of materiel.
The Argentinians were the first Latin American country to put a rocket into space with domestic technology.
https://en.wikipedia.org/wiki/Orión_(rocket)
Orión was the designation of a sounding rocket of Argentina, [1] which was started between 1965 and 1971 at CELPA, Mar Chiquita, Tartagaland Wallops Island.[2] In November 1966, three tests of the Argentine-built Orion rockets took place. [3] Developed by the Instituto de Investigaciones Aeronauticas y Espaciales (IIAE), [4] Orión marked Argentina's entry into the club of space-faring nations.[5]
In the 1970s there was interest in militarizing the space program. This accelerated after the Falklands War but there was work being done even before.
https://www.nti.org/learn/countries/argentina/delivery-systems/
In 1979, Argentina began to seriously embark on a missile program. Through the Swiss Consen group, Argentina contracted the German firm Messerschmitt-Bölkow-Blohm (MBB) to produce Condor-1, a single-stage missile capable of delivering a 400kg warhead over 150km. [11] Under the authority of Argentina’s Air Force (Fuerza Aérea Argentina, or FAA), the Condor-1 came to involve a complex consortium of “unprecedented complexity,” … By Janne Nolan’s account Condor-1 thus grew into one of several third-world missile consortia at least partially “fueled by illegal or quasi-legal transactions made through commercial firms or renegade governments.” [14] Work progressed at home as well, with the completion of a missile design and research center in Cordoba in 1981…
- Many satellite weapons enter orbit, which is a more sophisticated undertaking than just putting a rocket into space at the same altitude as a satellite. Orbit requires both the altitude and also lateral movement fast enough that the satellite keeps missing the earth as it falls. The Argentinians in 1982 could not put a satellite into orbit, but they could reach space.
In this alternate timeline, the 1982 Argentine antisatellite weapon uses their Condor sounding rocket. Rather than an explosive payload (they knew that it was likely their rocket would only be within a few km of the target, if they were lucky) they use a non-nuclear EMP device powered by an explosively pumped flux compression generator The electromagnetic pulse disables the satellite at a greater distance than would be possible with a conventional explosive.
It might be possible for Argentina to develop the capability to boost a payload to LEO satellite altitude in that time frame. It wouldn't have to achieve orbital velocity, just be able to get near the satellite before it fell back to earth.
However, one has to remember the reason Galtieri started the Falklands war: to distract the people's attention away from Argentina's dismal domestic economy.
So, while getting a payload into space, and attacking a satellite might be possible, Argentina did not have the economy to fund such an effort.
And if they did have the money to develop such a system, they probably wouldn't have started that war.
Also consider that most satellite data available to the UK, came from US satellites. Attacking them would have had far reaching consequences.
A more realistic scenario would be Argentina developing its own anti-ship missile technology. Far less expensive than ASAT, and far more effective for that particular conflict.
At the start of the war, Argentina only had a few Exocets, and shot almost all they had. If they had possessed more, and were able to take out the UK's two carriers, they could have defeated the UK invasion force, as the British would have had no air cover for their ships, or their troops on the ground.
That conflict was a lot closer than the outcome might suggest.
As with other technology, they would get it as soon as the US decided to sell or lease it to them.
Simple scenario: by the 80's Argentina has long been used by the US to help covertly with its 'dirty wars' in Latin America, epitomised by the famous School of the Americas. The US wants to extend their use of Argentina as a puppet, to take action against satellites, real or potential, launched by the Eastern Bloc. So the CIA fabricates an Argentinean rocket program, complete with famous escaped Nazi rocket scientists from the 40s (we all know they went to Argentina, Operation Paperclip notwithstanding), and uses it as a cover to transfer US ASAT technology to Argentina.
The Junta then has access to a weapon which it may or may not use as the US intended.
As an Argentinian let me tell you that there is a way Argentina could have that technology and, surprisingly, it wasn't that deviated from current history, it only needed 2 little "pushes":
USA decided to kill ALL the Germans scientist instead of going with operation paperclip: the brain power the Nazi had now needed a new place to escape, and Argentina was very welcoming to them. heck, in disclosed papers of the CIA they even said that Hitler actually escaped and came to live in Argentina, so it's not that much of a leap that they could choose Argentina instead of USA, and with them also comes the knowledge that made possible the Apollo program.
Argentina never went down the path of "Peronismo": Argentina was a country which received a huge influx of immigrants from the war-torn countries, having the same conditions as USA had as a "land of promises", which showed in his increasing economy before the 1930. Most historians claim that before the military coup that put Peron in power (which was made to avoid what USA considered the "lefties" coming into power) the central bank of Argentina was full to the brim with gold, part came from selling food to all the countries involved with the war (on either side), and part came as the price to let the Nazi escape here without asking questions. The new military government, and subsequent ones made a show of wasting that economic power on inefficient bureaucracy and plain theft.
After WWII, with every country exhausted because of the war, the economic power resulting from good trading and economic growth, and a new scientific personal ready and motivated to "recover" their place at the top of the world it's not far fetched to say Argentina would have turned into a new Superpower.
Of course this is Argentina we're speaking. Even if they made it it only takes a bad politician to set the whole country 50 years back. We're still dealing with the aftermath of what happened in 1930.
note: Some will say that things got worst for Argentina with the depression of '29, but that also hit the USA, yet they powered through it while Argentina failed. The key difference was the political stability USA had, while argentina went from coupt to coup until the 83
