President Donald Trump signed an executive order making Bitcoin the sole U.S. strategic digital asset reserve.The U.S. government holds 198,109 BTC ($17.33B) and aims to expand reserves without taxpayer burden.A digital asset stockpile will include XRP, Ethereum, Solana, and Cardano, but no expansion planned.The executive order also mandates a full audit of all government-owned digital assets within 30 days.