NASA has orbited and constructed a Space Station and it has been crewed non-stop. We may live in an age where we never know a time when there is not a human presence in space again.
That is no small accomplishment. To say that they have "not done much" does not make sense at all. Who has done more?
And bear it mind that Rutan can use all of the research and data from NASA that cost blood and money to get for free.
GMTA!!! :-)