Quite right Paul, Franco’s regime was brutal in suppressing opposition, but the had seen how officers from the Soviet Union behaved to soldiers under their command, and to prisoners of war, during the Spanish civil war.
There are many well documented instances of Soviet officers shooting their own men for seeking cover under fire instead of charging towars the enemy guns.
So as we have seen recently in Libya and Syria, it was a case of choosing a tyrant who loved Spain over tyrants who loved an ideology.