SpaceX Polaris Dawn spacewalk: Is the US breaking a 50-year-old space law?

It will be the first-ever spacewalk on a private mission. But does the US bear no responsibility for SpaceX's ambitions?

SpaceX Polaris Dawn spacewalk: Is the US breaking a 50-year-old space law?
It will be the first-ever spacewalk on a private mission. But does the US bear no responsibility for SpaceX's ambitions?