Jon Lieber, head of Eurasia Group's coverage of political and policy developments in Washington, shares insights on US politics:

How are Democrats going to finance their $2 trillion spending bill?

Well, I don't know. And the Democrats don't know either. The original idea was to undo a lot of the Trump tax cuts from 2017. This is a very unpopular tax bill that every Democrat voted against, but moderate Senator Kyrsten Sinema told the White House earlier this month that she's against any and all tax rate increases. This takes the top individual income tax rate going up off the table. And it takes the top corporate rate going up off the table. And it probably takes capital gains rates going up off the table. So, now the Democrats are scrambling to backfill that revenue that they can no longer raise through rate increases with other ideas. One of those ideas is a tax on the unrealized gains of billionaires.