Pence or Congress can do the right thing if either acts promptly
The Trump Insurrection should have consequences.

Option: Impeach. The president has sent an armed force to occupy the Capitol, indirectly causing the deaths of up to four people, whether by command or implication. Sounds like a high crime to me. In that bastion of liberty, Texas, a death resulting from a crime is called capital murder. Don't give me any BS about armament; several armed persons were arrested during the attempted coup. VP Pence becomes president for 14 days.

Option: Invoke 25th Amendment. VP Pence and a majority of the required subset of the Cabinet can take over the government by certifying that the president is incapable of serving. If you have not watched Trump's speech this noon, you should, and you will no doubt concede this is not a well man. And his beloved ploy of appointing "acting" cabinet members will work against him; such unconfirmed officials need not be included in the decision. Trump can protest and bring witnesses to Congress to say he is just fine, but in the meantime he will not be able to exercise power; that will take at least 14 days. Pence becomes president for 14 days.

In either case, if Pence pardons Trump, a case can be made for collusion, so impeach Pence, too, making Pelosi president for 14 days. To prevent what they will consider the worst possible thing that could ever happen, (R)s will keep Pence from issuing such a pardon.

During this interim presidency we could rest assured that Pence could not start a war or do anything really stupid, as Congress controls the purse strings and he would have no electoral mandate.

Do I think Congress can act? Not really. Do I think Pence will act? Not really. Do I think that is a shame? Absolutely.