Moore is a citizen of New Zealand, not the US.
...Stanek wrote that the agents – who said their department also investigates hate crimes such as those committed by white supremacists – asked “inappropriate questions clearly aimed at intimidating Andy, while also launching into a fishing expedition about me.” Agents reportedly asked her son-in-law whether Stanek had inspired his activism, whether she trained him, and if he got his ideas from her.
The grilling was occasioned because Moore used a bullhorn (possibly a local noise-ordinance violation) at a protest. Not exactly sedition.
Silly Moore. Crossed the border legally.