My view is that Trump's actions on China in 2020 are basically hollow and designed to preserve the Phase 1 deal and prop up the stock market.
The only reaction to the Bolton book seems to have been his signing the Xiuger act which happened the same day. The uniform condemnation of Bolton from other people in the room buries this I believe. Lighthizer was asked a "gotcha" question by Menendez and did seem candid and honest.
As to Trump's political calculations on Phase 1 and how they could change, the key overarching determinant is whether he is willing to crush the stock market. Any movement toward increased tariffs or restricting market access would be very negative for stock prices. He still talks about the market almost every day and thinks that it helps him politically.
I don't know the answer on that question (based on voter data) but I tend to believe that people voting for Trump based on China, immigration, and other non-establishment core beliefs he brought to the Republican mainstream don't own stocks and don't care about the market.
My view is that if Trump focuses on the S&P he will lose the election. If he refocuses on China's failings on the virus and general bad behavior he will win.