Saints players and other key sports and public figures are angry at Drew Brees for his anthem comments

Serious question, why do people consider it disrespectful to kneel during the anthem? Kaep said it was actually an ex marines idea to kneel because it’s peaceful. Can you still kneel and love America? Once again this question is genuine curiosity, anyone who turns this into an argument other than a polite discussion to answer my question will just be ignored.