Readers respond to Mrs. Clinton’s sharply worded Opinion guest essay. Also: Autism misinformation; President Trump’s trail of destruction.

Why has fighting and opposing Trump proved so hard? It’s not just because Republicans hold all the cards in government.

The Signal group chat is only the latest in a string of self-inflicted wounds by the new administration.

In Trump world, the rules apply only to other people.

Five years after founding The Times’s flagship newsletter, Mr. Leonhardt recently began a new role on Opinion, overseeing the editing and writing of the paper’s editorials.