Three days before his 2025 inauguration, Donald Trump launched a cryptocurrency called $TRUMP. That May, he dined with 220 of its largest holders, some of whom bought up the coin expressly to secure invitations. In October Mr. Trump pardoned Changpeng Zhao, a Binance co-founder who had been convicted of violating money-laundering laws. Binance had assigned a team to develop the stablecoin for World Liberty Financial, a crypto venture tied to the Trump family. The undertaking netted Mr. Trump hundreds of millions, part of $1 billion in crypto gains, while most token buyers lost money. Last year Paramount agreed to pay...