The Cuba of Europe

I don't get this obsession with Ireland.
I can't speak for the others, but I just thought that a rather poor agricultural island with its own guerilla groups that definitely lean towards the left(both cuba and ireland) was a good comparison. Mainly, I just want to get Ireland involved in the cold war. and hey, look at the bright side. A communist Ireland means the Plastic Paddies won't be so numerous and irritating.;)
 
If the communists took power in Portugal during the revolutionary period, there would have been a civil war with socialist[1], social democrats[2] and centrist[3] politicians moving north[4] and establishing a temporary capital at Oporto.

Most armed forces (and an even larger proprtion of the civilians) would side with the legitimate government (in Oporto), even if the south could be taken by the far-left (always taking into account that the control would not equal support from the civilians - genuine popular support for communists would be in the parts of Alentejo, where there's no tradition of small private property, and industrial suburbs of the Lisbon Metro area).
The centre and north, with its small private properties, and Catholic Church influence, never saw any interest in communist ideas. The same is valid for the Azores, Madeira, the centre south and parts of the south(parts of Alto Alentejo and Algarve, as well as the area close to the Guadiana river and isolated places elsewhere), although the Lisbon area and the non-communist parts of the south could be occupied by the far-left.

The west, in particular the USA, would send arms to the western oriented parties (there were guns distributed* to the socialist party, just in case). The far-right would attack the far-left with support from Spain (and based in Spanish territory), and tactical acceptance of the democratic parties and loyalist armed forces.

Very likely Spain would intervene to help the anti-communist forces, but it would probably be in cooperation with the pro-democracy forces (I know it sounds strange, but in OTL, Franco expressed extreme caution against attempts to interfere in Portugal with an armed intervention against Portugal perceived slide to communism - a matter of perception but not actual leftism in Portugal - he knew us well).

The Azores and Madeira would probably declare their independence. Their small embrionary independence movements of the time were motivated by fear of the communism, and propped by some politicians in the USA (but not the US government), although if the US government decided to endorse those declarations of independence, that would not go well with the Portuguese government, nor with most NATO members.
Those regions, if independent, would rely very heavily on foreign economic support.

Another aspect would be the political violence.
While in the south, the centre-left and the right would be persecuted during the short term of communist rule in the south, the far-left would be more violently targeted in the north than in OTL. In the south, all properties and sectors of the economy would have been nationalized, during the communist rule over the south.
In the north and as the government forces move south the Communist Party and other afilliated organizations[5] would have been banned.
Other organizations (like unions[6], public administration, media, the military, etc) would have been purged from the far-left.

I hope this helps.:)

* Can't remember who did it.
[1] - respectively a socialist democratic party (and probably other minor socialist parties, like the now defunct Movement of Socialist Left)
[2] - respectively a party at the time ranging from moderate social democrats to conservatives - a case of sisnistrisme
[3] - respectively a party with centrists, christian democrats and conservatives - another case case of sisnistrisme.
[4] - there were plans for it in OTL.
[5] - MDP-CDE (a communist controlled far-left party) and any other party who might assist in the coup.
[6] - like the then only trade union center, CGTP (Confederação Geral dos Trabalhadores Portugueses), who since the Carnation Revolution has always been majoritarily communist.
 
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