Will we get an agreement on the “fiscal cliff” before year’s end? Even after Friday’s developments, which included a meeting of congressional leaders at the White House, I really don’t know—and neither does anybody else. But when the deal materializes still matters less than what the deal entails.

Let’s review what happens on January 1, at least officially, if Congress and President Obama don’t act:

Tax rates on all incomes would return to what they were during the Clinton era, before the Bush tax cuts reduced rates. Automatic spending cuts to a wide variety of agencies, including the Pentagon, would take effect—a punishment Congress imposed upon itself, by failing to find alternative spending cuts that it had vowed, in 2011, to find. Extensions of refundable tax credits for the working poor, families with children, and people paying college tuition would expire, as would an emergency federal program that provides extra unemployment benefits and a temporary reduction in payroll taxes. Medicare would reduce what it pays doctors and income tax filers would have to consider whether they fall into the “alternative minimum tax,” resulting in substantially higher liabilities.

Lots of people would feel the impact personally—their paychecks would shrink, government services would become less available, and so on. In addition, the policies as a whole would reduce the money going into the economy, causing it to slow down and quite possibly fall back into recession. That’s obviously not an outcome anybody wants.

But would all of these things happen right away? Is January 1 truly the make-or-break date that so many politicians and pundits seem to think? That’s a lot less clear.