Shortly after the tragic events of 9/11, the nations of Toobworld agreed upon a treaty that would ban the uses of invisibility, miniaturization, and teleportation. (We learned about this from Tuesday's episode of 'Eureka' - "Sight Unseen".)
A workable teleportation system - developed by Terrans, that is, - will be over a century from completion. (At some point prior to 2121, Emory Erickson will have had the basics for a transporter worked out, but the first one in operation would be ready prior to 2139. We learned this in the episode "Daedalus" of 'Enterprise'.) However, there have been a few alien-created teleportation devices developed and used only by them (as evidenced by the personal device used by Blon Slitheen in the "Boom Town" episode of 'Doctor Who'.)
Miniaturization, on the other hand, has been around on Earth for over a century. The concept was developed along different paths, beginning with the experiments by Dr. Miguelito Loveless ('The Wild, Wild West' - "The Night Of The Raven"). There is also the work of a mad scientist known by the alias of 'Dr. Shrinker', as well as research done by the British government under the guidance of Professor Rushton ('The Avengers' - "Mission... Highly Improbable"). All of that would have to have been abandoned due to the treaty.
It's because of that treaty the US government would have had to capture such figures as Dr. Peter Brady ('The Invisible Man'), Darien Fawkes ('The Invisible Man'), Sam Casey ("Gemini Man") and Dr. David Westin ('The Invisible Man') in order to prevent other nations from declaring war. Each of them has been rendered invisible by science and so, because of the treaty, the government might have had to take a "Fail-Safe" option - killing them - to prevent their escapes. It's no wonder Claude has taken an alias and gone underground in order to stay alive (as seen during the first season of 'Heroes')!
The brain pool at Global Dynamics in Eureka was able to cure Sheriff Jack Carter of his accidental case of invisibility, but had they failed, there wouldn't have been a need to kill him. The formula used to create his invisibility was highly toxic due to unstable radioactive elements and would have killed him anyway in 24 hours. That would have been satisfactory for the other nations, but luckily it didn't have to come to that.