LOS ANGELES -- Former White House adviser Steve Bannon says there has not been a more destructive presidency than George W. Bush's. 

Bannon delivered a scathing criticism of the former president after Bush this week denounced bigotry in Trump-era American politics, warning that the rise of "nativism," isolationism and conspiracy theories have clouded the nation's true identity. 

• "60 Minutes":  Bannon declares war on the GOP
  

Bannon told a capacity crowd at a California Republican convention in Anaheim that Bush "embarrassed himself."

In his remarks in New York, Bush warned of a nation in which discourse has been degraded by "casual cruelty," where bigotry is emboldened.

Bannon says Bush has no idea whether "he is coming or going, just like it was when he was president."

Bannon also renewed his criticism of the Republican establishment in Washington, saying the permanent political class is one of the great dangers faced by the nation.

About two dozen protesters gathered in Anaheim Friday evening, chanting and holding signs that urged "BAN Bannon." One sign had a Nazi swastika.

The demonstrators were behind steel barricades, well away from people entering the convention site. There were no arrests.