This guy is part of the group of crazies holding the wildlife refuge hostage. It's a very complicated chain of reasoning that probably isn't worth reading, but here's my attempt at it anyway.

There's a subculture of far-right conspiracy theorists who posit a bizarre alternate shadow legal system. Their ideology can be rather complex and varied. A common theory is that the federal government doesn't have the right to levy an income tax; this was a legitimate constitutional question at one point and an amendment was passed just to ensure the law could not be stuck down, by conspiracy theorists argue for one reason or another that the amendment was never really passed and it's all just a conspiracy to illegally collect income tax. Except it's not really illegal because when you're born the government creates a corporation with the exact same name as you and that corporation is taxed. And in fact all of your income and all of your bank accounts are actually going towards the secret corporation the government keeps. Now, the theory goes, a birth certificate is a legally binding document and if you alter that document in some way, you're altering the law. So you simply write "sovereign citizen" under your name under your birth certificate and now the corporation goes away and you don't have to pay income tax. In fact, you don't have to abide by any of the rules the illegal government makes you think you have to follow because the real government goes by different rules.

The federal government in the secret real legal system has less legal authority than the states, which is why they have to resort to all this trickery and legal technicalities to continue oppressing the people with their taxes and what-not. So the state troopers are the only real authority he recognizes.

The wildlife refuge he was headed towards has been "annexed" by sovereign citizens because it's a federal wildlife refuge, except the federal government can't actually own land that belongs to the state and they, because they wrote "sovereign citizen" on their birth certificate can just take it over if they want.

So how do they reconcile their ideology with, you know, the real jail time that some of these men have undergone for defending themselves against trespassing social workers and forest rangers (and in particular, arson to an occupied federal park)? FUCKING NAZI GERMANY, MAN. IT'S JUST LIKE THE NAZIS.