i was also trying to understand this better recently and the best summary for me was:
“The United States can assert jurisdiction if the ‘acts’ occur in the United States or there are substantial ‘effects’ of acts outside the United States [are] within the United States,” he told Sputnik. Zagaris referred to the use of U.S. mail and wires for meetings and the role of the U.S. financial system “to make and invest some of the bribes” as potential triggers for U.S. jurisdiction, including American money laundering laws.
Zagaris said that several U.S.-based organizations are involved, including a sporting clothes company (we assume it is Nike, which is based in Oregon) and FIFA’s Latin American subsidiary, CONCACAF (based in Miami Beach).
A third reason for U.S. involvement is that bribes allegedly made in connection with the 2022 World Cup had a direct impact on the U.S. because the U.S. was among the losers to Qatar for that designation.
Switzerland May be Venue for FIFA Corruption Case's Legal Proceedings / Sputnik International