Does the President Have a Right to Not Encounter Disagreement?

Alex Young and Leslie Weise attended a presidential forum on Social Security in Denver back in 2005 and were ejected after security noticed they had an anti-war bumper sticker. The forum was funded with taxpayer money.

From the briefing for the White House:

The president’s right to control his own message includes the right to exclude people expressing discordant viewpoints from the audience.