NFL player and human rights campaigner Chris Kluwe has written an impassioned opinion piece in which he addresses the question of why, as a straight man, he supports the gay community.

A punter for the Minnesota Vikings, Kluwe has been vocal in his support for equal marriage, and gay rights, as well as standing up for human rights as a whole.

Writing for the Huffington Post, in the Gay Voices section based around the idea of “fearlessness”, Kluwe starts by saying “it’s the right thing to do”. He goes on to denounce “bullying, intolerance and bigotry”, and condemns those unwilling to attempt to empathise with people in the gay community.

He then goes on to quote a poem by Martin Niemoller, which encourages minorities, social and political groups to stand up for one another.

Concluding, he writes: “Why do I speak out in support of gay rights, of all rights to equality? Because if I don’t, then who will be left to speak for me?”

Chris Kluwe made the headlines in September when he defended Brendon Ayanbadejo, formerly of the Baltimore Ravens, against a call from Delegate Emmett C Burns Jr, to reprimand Ayanbadejo, who recorded a video for a gay rights advocacy group In October 2011.

In a response to Burns, he wrote: “I can assure you that gay people getting married will have zero effect on your life. They won’t come into your house and steal your children. They won’t magically turn you into a lustful cockmonster.”

He and Ayanbadejo wrote an amicus brief, and filed it, urging the Supreme Court to act against legislation preventing equal marriage.

Yesterday, Kluwe joined Michelle Obama, and thousands of others, in tweeting a message of support for the US’s first openly gay player in any major team sport, Jason Collins, of the NBA, who came out in a piece for Sports Illustrated magazine.

The full text from the Huffington Post, on which Kluwe tweeted: “I wrote a thing (on Friday, it went up today, so don’t get your panties in a twist). It has words,” is available to read below: