Biden raises some valid concerns about Trump's role in the January 6th Capitol riot and his controversial statements regarding the Charlottesville events. However, he also engages in ad hominem, straw man, appeal to fear, and quoting Trump out of context, which undermines the overall strength of his arguments.

1. straw man via quotation out of context • Biden misrepresents Trump's statement about "very fine people, on both sides" at the Charlottesville protests by omitting the context in which Trump explicitly condemned neo-Nazis and white nationalists.

[Trump] said, I think they're fine people on both sides.

What American president would ever say, Nazis coming out of fields, carrying torches, singing the same anti-Semitic bile, carrying swastikas, were fine people?

By implying that Trump was praising Nazis, Biden attacks a distorted version of Trump's words rather than engaging with the nuances of his actual statement. Here is Trump's quote in its original context:

Excuse me, they didn't put themselves down as neo-Nazis, and you had some very bad people in that group. But you also had people that were very fine people, on both sides. You had people in that group... and I'm not talking about the neo-Nazis and the white nationalists, because they should be condemned totally. But you had many people in that group other than neo-Nazis and white nationalists, okay?

2. ad hominem • Biden attacks Trump's character and morals instead of addressing the substance of his arguments.

You have the morals of an alley cat.

While Trump's character may be questionable, this personal attack does not directly refute his claims or answer the question at hand.

3. quotation out of context with appeal to fear • Biden quotes Trump out of context so as to suggest that the former President warned or threatened political violence.

And now he says if he loses again, such a whiner that he is, that there could be a bloodbath

The full context wherein Trump used the word "bloodbath" is in a conversation about the economic prospects of the US auto industry and auto workers:

Trump, March 16: China now is building a couple of massive plants where they’re going to build the cars in Mexico and think, they think, that they’re going to sell those cars into the United States with no tax at the border... ​No. We’re going to put a 100% tariff on every single car that comes across the line, and you’re not going to be able to sell those cars. If I get elected. Now, if I don’t get elected, it’s going to be a bloodbath, for the whole — that’s going to be the least of it. It’s going to be a bloodbath for the country. That’ll be the least of it. But they’re not going to sell those cars.

When Trump said, "It's going to be a bloodbath for the country," he appears to be discussing the potential economic consequences of not being elected, specifically in relation to China's car manufacturing plants in Mexico and the proposed tariffs. By omitting this context, Biden's statement implies that Trump was referring to a violent outcome rather than an economic one, which is not supported by the full context of Trump's statement.