Did a WA State Rep just endorse slavery?

It was bad enough when WA State Rep. Matt Manweller said a $0 minimum wage would be "perfect". But when a voter pointed out in an email that $0 wages haven't been allowed since the Civil War, this is how Manweller responded: 

When I first glanced at the email, I couldn’t believe he had really written those words. This politician had the chance to modify his minimum wage statement — instead he put his foot in his mouth even more deeply.
— Bill M., who received the initial email from Rep. Manweller

Ummm… did a Washington State Representative just endorse slavery? In 2017?

Manweller has long been an outspoken opponent of higher wages, paid sick days, and other basic rights for workers. He's spent time on the floor of the State House insulting workers who testified before his committee. He said $0 was a "perfect" minimum wage.

And now he seems to be saying that eliminating slavery belongs on a list of the "mistakes" made during the Civil War.