> If Democrats win they could extend them

And what happens to the debt/deficit then? You know, the thing that the GOP constantly complains about but always makes worse?

The GOP loves to cut revenues (taxes, especially for top percentiles):

* https://en.wikipedia.org/wiki/Starve_the_beast

They love to cut revenues and explode the debt. "The party of fiscal responsibility."

If Democrats win the presidency, they would still probably need cooperation from Republicans to get an extension through Congress, which means that there are no good options for the Dems.

Just in time for Republicans to blame them for making the debt worse. It's all so cynical.

Yes but this policy is absolutely terrible, so it seems unlikely they would

but it's a very stupid policy.