In my play groups for Global 1940 we have been playing where if you attack a true neutral only the true neutrals in the same continent as the one invaded will turn pro-axis/allies
It doesn’t really make sense that if America attacks Colombia. Switzerland, Spain, Portugal, Sweden, Turkey, Saudi Arabia etc. become pro-axis. It also makes the game more interesting in that players are bolder and won’t feel so bad about taking a far away Neutral.
I realize that the original rule is so that you play more historically accurate games and won’t be attacking any neutrals but those guys are just so tempting sometimes!
I Also think that with this rule the fate of African true neutrals and MIddle east true neutrals are shared so that if the british attack Angola. Mozambique, saudi arabia and afghanistan will turn against you.