Around 100 protesters calling for the woman accused of killing Harry Dunn to return to the UK 'shut down' the Northamptonshire airbase where she was based for a couple of hours on Saturday (January 4).
People from all over the country and their homemade placards joined the teenager's family to block the entrance and exit of RAF Croughton over the Anne Sacoolas scandal.
Family spokesman Radd Seiger believes the protest proved they are capable of closing down all American operations in Britain if the US does not co-operate and send her back.
"We wanted to let the US authorities know that we will shut these bases down if you don't agree to keep us safe and abide by our laws," he said.
"I think we proved beyond any doubt that is what we can do as we shut it off for two hours and I felt we made a point - that's all we wanted to do."
Harry, 19, died in hospital after the crash with a car while riding his motorcycle on the B4031 between RAF Croughton and the village of Croughton on August 27.
Mrs Sacoolas refuses to come back to Britain on her own accord after claiming diplomatic immunity through her husband and flying to the US, despite initially co-operating with police.
The UK Government is working on extraditing her but the American administration has expressed its dismay at the decision to charge her and previously told Harry's family she would never return.
Mr Seiger said people from as far as Aberdeen and Norwich, as well as plenty of locals and those from Northampton, came to support him and members of Harry's family at the protest.
The fact so many people came with such short notice made him believe 'thousands' would come if even more organisation was put into another protest, if need be.
"We don't want to disrupt the goings-on at an airbase, our quarrel is not with the base, it is with those in Washington that are teaching people at the base, 'you don't have to worry about committing crimes in the UK as we will take you back'," he said.
"We know President Trump has a stake in this and has a choice to make: send her back, never do it again and commit to doing the right thing. If not, then we will shut you down."
Mr Seiger insisted if his own talks with US delegates later this week go well then there would be no need to continue protesting, but if they do not co-operate, then they will not stop until they do.
"We are never going away and we're never going to let this happen to another family again," he said.
"Charlotte [Charles, Harry's mother] made that promise to Harry in the hospital that she will get him justice, and we will not stop until we do."