Hey. Genius. When the President of the United States has a path laid out by the Secret Service, they have the responsibility to avoid what happened to Martin Luther King, JFK, RFK and Reagan.
You have it backwards. Half the job of the secret service is to tell the president where they can't provide adequate security. Which was the excuse Trump gave for not visiting the Belleau Wood marine, cemetery in Germany.
Trump chose to go into the belly of the beast against all advice, and the secret service was forced to use extraordinary (read as illegal) means to carry out clearing Lafayette park prior to the curfew.