Although there were still Canadian Maple Leafs available, the US Government decided to help fill the void by making their own coins. This void was especially large during the 1980s due to various factors such as US-Russia relations, unemployment, and problems with Social Security.
As a result, the US created The Gold Bullion Coin Act. This act required that the U.S. Mint start producing 22-karat gold bullion coins in different sizes and denominations ($50, $25, $10, $5). The Act specified the exact dimensions and designs of the coins. The Act mandated that enough coins be produced to meet the public's demand assuming that the resources were available to meet said productions numbers. For example, the 2009 Gold Coins were cancelled as the mint could not keep up with the demand caused by the Great Recession of 2008.
Other rules set by the Act include using only natural deposits from U.S. territories within 1 year of being mined, not paying more than the average world price for gold, and using profit obtained from the sale of coins solely for reducing the national debt.
This legislation was a groundbreaking achievement. It got the U.S. a piece of the national and global coin market and established one of the most popular gold bullion coins ever: the American Gold Eagle.