In order to make sure the rich are paying their fair share in taxes, President Joe Biden says the IRS just needs two bits of information: all the money that goes into your bank account, and all the money that comes out.

That's how Biden pitched his plan for a more comprehensive financial surveillance state—all to catch those nasty tax-cheating rich folks, of course—during a speech from the White House on Thursday afternoon.

The plan "will give the IRS the resources it needs to keep up with the lawyers and...