September 17 is also Constitution Day, so Antifa is making a direct affront to the entire existence of the American Republic.
"Constitution Day commemorates the formation and signing of the U.S. Constitution by thirty-nine brave men on September 17, 1787, recognizing all who are born in the U.S.
or by naturalization, have become citizens."
https://constitutionday.com/
"Constitution Day September 17th (or Citizenship Day, formerly observed the third Sunday in May) is an American federal observance that recognizes the adoption of the United States Constitution and those who have become U.S. citizens. It is normally observed on September 17, the day in 1787 that delegates to the Constitutional Convention signed the document in Philadelphia."
https://en.wikipedia.org/wiki/Constitution_Day_%28United_States%29