Southern CA high school teacher is heard bashing the military

Southern CA high school teacher is heard bashing the military. Is such behavior acceptable in America and especially a high school government class?

California teacher slams military members as ‘lowest of our low’ in classroom rant caught on video
http://www.foxnews.com/us/2018/01/28/california-teacher-slams-military-members-as-lowest-low-in-classroom-rant-caught-on-video.html