The AIC definitely existed. It was organized by a group of American business owners hoping to concentrate capital in New York.

Boiled down, anyone can make a million and lose it selling widgets. To get rich and stay rich, you take a percentage of everyone else's money. The AIC tried to capitalize (pun intended) on the flood of money leaving Europe to pay for war materiel, in order to topple London as a financial capital and replace it with New York. Banking, shipping, insurance... these were the slow but steady sources of true economic power, and what the founders of the AIC wanted to take control of.

The AIC are conspiracist bogeymen because of their involvement in the early days of the Russian Revolution, but they're far from alone. The U.S. Chamber of Commerce did its best to drum up investment in Russia after the Czar fell in early 1917 (well before the Bolsheviks seized power). President Wilson ordered massive aid to the new provisional government, and advisers and salesmen flooded the country, hearts pounding over Russia's resources and its endless supply of trainable, low-wage labor.

The AIC and other companies invested heavily in Kerensky's Russia. When the Bolsheviks took power, U.S. investors lost huge amounts of money. They tried, with little success, to get their money back by playing nice with Lenin. It didn't work.

A lot of American businessmen were also caught slipping money to Bolshevik leaders before they toppled Kerensky, and even before Kerensky toppled the Czar. Why? Not because they were setting up some international Marxist-feudal octopus. It's simpler than that.

They saw the Czar tottering. They wanted to help him totter, and to have influence over the people who knocked him down. It wasn't a massive conspiracy. It was a "consulting contract," a gentleman's bribe, and it was standard operating procedure then and now throughout most of the world to slip a politician a bit of money in hopes of making a profit off that friendship in the future. Money went to every party in the Duma. It's just that during the Red Scare of 1919, no one investigated old donations to Kerensky.