It's hard for people to agree on a subject like this. I also feel like history should be preserved, no matter what the item represents.
Good point about our country. All those "cool arrow heads" and antique weapons have a history, too. That arrowhead in your home could have been used to murder a sleeping woman or a terrified child when a neighboring tribe raided the camp. Maybe they were fighting over land and an entire innocent village was wiped out. That arrowhead was instrumental in changing history and could have contributed to the death of a human life.
That beautiful firearm from the 1800's could have killed countless african amercans in hate crimes. That "antique" also changed history in a way nobody will ever know, because it's not inscribed on the weapon. But I guarantee almost every one of us has a piece of history that killed a person or is otherwise associated with some horrible act on a human being. The only reason people hate Nazi items is because that Swastika is etched into our brain to represent hate.
All pieces of history need to be preserved, no matter what the association. I'm sure plenty of people think that medieval sword or ancient dagger is just amazing. Why not hate those? Those were absolutely used in battles over land and battles of religion. Where thousands, sometimes millions, of people were hated and slaughtered. There's no Swastika on those items so we find them fascinating. I find Hitler disgusting, but these items need to be shown to future generations. So that when they ask the questions...
How big was this?
How did it feel?
What did it look like?
What was it made of?
They won't have to see it on a piece of paper in a history book. They can feel it, they can see it and they can understand history. Maybe if they see these pieces of history, they won't make those mistakes in our future.