First of all why it should be stopped by the government???
That's the right question. Since we don't really know everything about Bitcoins origins, it might even have been a project run by an agency.
Doesn't matter. The community runs it todays.
They can only try but there is no guaranty that they can, so they would not even try to do that they can do that when it was just starting out and they can save their resources but it's now very popular and very viral, it would take a huge resources to stop it and of course investors will not let government stop them, there is big money to be made here.