Although I have issues with anyone that would buy Nazi memorabilia (I am not Jewish, but I am human), I agree that his intent probably isn't to take this small sword he bought and go on a stabbing spree. That won't matter though; the moment a pre-trial services officer sees this thing in his house during routine searches that are usually a condition of federal bail, his bail will be revoked at a minimum, and he may face new charges.
He's going out of his way to thumb his nose at the Court; they tend to frown on that.
It does kinda depend on the reason for buying Nazi memorabilia.
For example, if you are ever in the northwestern part of the mitt of Michigan, I highly suggest visiting the Jim Crow Museum of Racist Memorabilia: http://www.ferris.edu/jimcrow/
But I'm sure the most common reason for someone who would buy a Hitler Youth knife is to be edgy.
I have a Nazi proof-marked Mauser K98 rifle. I like it much more because it was later bought by the IDF, rebarreled to 7.62x51mm, and marked with the IDF star. There are a lot of reasons to own such things.
He's going out of his way to thumb his nose at the Court; they tend to frown on that.