In Axis and Allies (as in the real war), Germany and Japan together have more industrial power, represented by industrial production certificates (IPCs) than Britain and Russia combined. Hence The US holds the balance of power.
Although the game is still tilted in favor of the Allies, it is much closer than in "real life" because US industrial capacity has been reduced by almost two-thirds. In fact, bidding systems have shown that if you give the Axis a one-time boost of only 12 IPCs at the beginning of the game, it would be even, assuming that Russia is not allowed to attack the first turn.
Could the game be balanced by reducing America's strength just a bit more? Specifically by taking away 1, 2, or all three of the 3 IPCS per turn that the US receives from Brazil? (This would reduce her IPCs per turn to 35, 34, or 33 respectively. Even allowing for the factors of time and distance, might this not be equivalent to the "one time" boost of only 12 IPCs to the Axis at the beginning of the game?