Yesterday was National School Walkout Day in the US. The walkout lasted 17 minutes, to remember the 17 victims of the massacre at Stoneman Douglas High School last month. There were hundreds of videos of students taking a knee outside of classrooms, making speeches and brandishing placards made at home.

But, some had a lot less support. At The Wilson Preparatory Academy school in North Carolina, out of 700 students 16-year-old Justin Blackman was the only one to walk out in solidarity for the cause. In a video he tweeted, he filmed himself walking out into an empty street.

“Hello Twitter, there’s going to be like six people watching this hopefully. It’s National Walkout Day, I’m the only one in my school out here. No one here but me. So I’m just gonna be chilling here for the next 15 minutes”

Fortunately for Blackman, there were more than six people watching, the video has amassed 4.44 million views so far, and has been retweeted by people all over the world who admire his bravery and commitment. He was even thanked by a survivor of the Sandy Hook school shooting and praised by Wrinkle in Time director Ava Duvernay.

She shared the video with a Martin Luther King quote as the caption: “‘The ultimate measure of a man is not where he stands in moments of comfort and convenience, but where he stands at times of challenge and controversy .’ - Dr. Martin Luther King, Jr.”

He later told CNN that he had spoken to his classmates about the walkout earlier that day, but “they didn’t seem to know about it”. “Now, I truly know that one person is all it takes. No matter the age, skin colour, gender – it doesn't matter,” he said.