Jon Lieber, Managing Director of the United States for the Eurasia Group, shares his insights on US politics this week:

Why wouldn't the president want to debate Joe Biden?

Well, I think the president does want to debate Joe Biden, but he wants to do it on his terms. He wants an in-person debate where he can try to dominate and overwhelm Biden and push him into having what looks like a senior moment, to help make the case that Joe Biden is too old to hold office. The Commission on Presidential Debates has offered a virtual debate where they can mute Trump's microphone and that's the format just doesn't really work for him. So, probably this debate is canceled. We'll see what happens with the third.