Because USA needed another NA, probably, and they didn’t want to give them Atomic Weapons? 😛
I dunno. Basically it just says that infantry can move two zones like tanks and may blitz. Not overly useful for America, but it does help.
A question came up while playing this game regarding Russia’s National Advantage, the Non-Aggression Treaty between Japan and Russia. If Japan attacks Russia in multiple territories at once, do they get 4 additional infantry in only one territory, or does each territory that is attacked get 4 infantry? The rule is not entire clear about this. It could be read either way.
“The first time in the game that Japanese forces attack any red territory, you may place four infantry from your inventory in that territory for free before resolving combat. If you attack Japan before it attacks you, you lose this advantage.”
From the Revised FAQ:
"Q. The Nonaggression Treaty allows the USSR to place four units in the territory Japan attacks
first. What if the Japanese player attacks two or more red territories on the same turn?
A. In that case, the Soviet player chooses which of the territories being attacked gets the four infantry."