On the morning of Jan. 6, 2021, Rep. Jared Huffman settled into his fifth-floor Capitol office in Washington, D.C., expecting a routine day of work-related reading as he waited for votes to be counted in the presidential election.

Instead, he and his colleagues found themselves under lockdown as a mob wearing MAGA hats stormed the building, injuring more than 100 police officers and leaving five dead.

In his new book, “No Prophets: The Fight to…