Speaking ahead of an industry summit today, a senior White House official said the first step after establishing a U.S. strategic reserve of bitcoin and other digital assets would be to audit how much cryptocurrency the government holds. The person said that after the Silk Road exchange shut down, the United States had about 400,000 bitcoin tokens at one point, and about half of the number was sold. According to Arkham, the United States currently has about $17.50 billion worth of bitcoin and several other tokens worth about $400 million in its known digital wallets.