Last I checked, you can build a flame thrower pretty easily, and it's legal to own (at least in some places, probably not
your state where buying a diesel-powered truck is illegal) up until the point at which you use it on someone or something.
Radioactive material and other deadly substances, such as sarin (made from castor beans,) mustard gas (made from French's yellow mustard) and C-4 (made from poop,) requries strict licensing to possess. I'm pretty sure you'd get vetted out of that process, buddy... no offense.
Just as with the War on Some Drugs, I have no problems with you having whatever weapons you wish as long as they are owned and used in a strict licensing and enforcement scenario.
The Second Amendment was ultimately intended to allow for protection of American citizens from their government. It was a given at the time that guns came in handy when the time for protection of one's life and/or property became at stake due to the imposition of another citizen or a group of them, and that's not at all addressed by the amendment. That assertion is easily proven by noting that NONE of the protections in the Constitution or the Bill of Rights restrict interpersonal activity, but rather only the actions of the government upon it's owners.
Let me repeat that in less Preechr-like prose: The Constitution only tells the government what it can and cannot do to you, not what we can and cannot do to each other or to the government. Your actions are restricted by laws passed by Congress, which are checked against Moral and Constitutional authority by the executive and legislative branches, respectively.
Now, if you really want to discuss Gun Control, please reference
http://justfacts.com/gun_control.htm first. It's actually a rather boring argument.