Cryptocurrency has become a global phenomenon in recent years, even as the technology underlying it continues to evolve. As consumers around the world have flocked to cryptocurrencies, the United States  has begun to face a classic case of "the innovator's dilemma"— a situation where an established leader can lose out by failing to keep up with technological evolution. Though the U.S. dollar remains king, U.S. agencies have been late in adapting to an increasingly digital financial system compared to countries like El Salvador and the Central African Republic, which have adopted Bitcoin as official currency.