No they don't actually. Not the norm for SSBI.

Only one I ever got in 30+ years was when I went TDY to a three-letter agency.

Polygraphs are not used to find out if you lied on your app, they are used to screen for hostile infiltrators (spies or organized crime). That's because they are so ambiguous as to be useless for a question like "did you smoke a joint in HS"? But an infiltrator will have a broad false identity, LOTS lies woven into a web and a polygraph can help a skilled operator pick that apart. He can't conclusively say that you lied about the joint, but he can conclude that there's a pattern of red flags when you talk about your high school and college years.

Law enforcement commonly uses them to screen candidates, especially the feds. But there's a very wide grey area in the interpretation of those things, and I think the issue with CPB is they erred on the side of extreme caution, resulting in few passes. To the point of ridiculous.

I get it that DEA/FBI might be screening some kid that they have zero professional history on, but military guys with clearances and a decade+ track record in the mil?

Smoked a joint in JHS =/= cartel sympathizer.