In the midst of the Falklands War, Argentinian Admiral Jorge Anaya authorised on 2 May 1982, the blowing up of a British Royal Navy transport ship and a frigate near Gibraltar. The group that carried out this attack were ex-guerrillas who had been sent to Spain expressly for this purpose and were posing as fishermen.
The operation was carried on successfully resulting in hundreds of deaths. Two of the three operatives (the third was military attache) were captured by the Spanish police. They publicly claimed responsibility for the attack and although they were formally opposed to the Argentinian government, they stated that "this is the time for unity of all the Argentinian people against the British aggressor who has occupied part of our land for centuries."
With the attacks now having spread to Europe, the UK government decide not to limit its operation to the Falklands or the High Sea but ask the armed force to draw up plans for an attack on Argentina itself.
In the UN, most European countries denounced the escalation, but stopped short of condemning Argentina beyond the original invasion. Despite much backroom diplomacy by various countries to try and reach some sort of peace settlements, Great Britain declared war on Argentina two days later.
Peru, who until then had been one of the major proponent of a peace deal, called on regional solidarity. Both Peru and Brazil followed this by pledging that should mainland Argentina by attacked, they would have no choice but to answer in kind. Other countries (most notably Mexico) offered non-belligerent aid to Argentina in the form of medical supplies and personnel. Both Bolivia and Cuba made speeches in the UN denouncing the UK, but neither proved ready to send in troops.
The Gibraltar Bombing
In our timeline, the Admiral had called off this attack in fear of destroying the Peruvian-backed peace talk going on. Only a few hours later, the British sank the Argentinian gunboat Belgrano, killing more then 300 sailors. The operatives then had to wait a month before a suitable target was found. Unfortunately for them, the British had, by then, going wind of the operatives and told the Spanish who arrested and deported them before they could attack a ship.
Now, *there* the British sub might have simply found his target half a day earlier and the operation would have gone on.
Declaration of War
Even though we talk about the "Falkland War", officially neither countries was in a state of war with the other. The UK stated they were defending a dependency (Falklanders only gained full British citizenship in 1985) and Argentina stated they were reclaiming lost territory. The UK had held off attacking Argentina proper but a bombing closer to home would have forced the hand of the government with the British people probably asking for a tits-for-tats response.
One interesting aspect of the conflict is in regard to the Rio Treaty which state that any attack on one of its member (which include most of South America) would be answered by all. Since Argentina was itself the one who attacked first, it wouldn't forced its members to take any actions but on the other hand, it might still be used as an excuse by some for propaganda purposes. Also, the fact that the USA clearly favoured the UK side might split allegiance.
Many observers have commented on the fact that beside the avowed reasons given by all participants in the war, one unspoken reason was shared by all: bringing together the various factions on home soil and thus, bolstering the reigning local government.
- France (non-belligerent aid)
- USA (non-belligerent aid)
After the decolonialisation of past decades, about the only oversea territory left to Great Britain were those inhabited (like the Falklands) by people of English descent (unlike former colonies where the British ruled over native population). Gibraltar's status for example was still disputed by Spain and a show of strength in one part of the world, it was felt, would probably dissuade similar attempts elsewhere.
The reason why France and the USA intervene was similar: both had oversea territories claim by others, by helping the UK, they helped themselves. Obviously they couldn't do it directly, France had sold much of the equipment used by the Argentinian army and the USA, who generally preferred local dictators in South America to European intervention, was part of various pan-American mutual help treaties.
Chile had territorial dispute with Argentina regarding the Picton, Lennox and Nueva islands as well as the sea located south of Tierra del Fuego. Joining the British coalition might give it the possibility to invade the islands.
- Mexico (non-belligerent aid)