I apologize, but I am surprised that you did not know about this very common Hate Symbol. It dates back to the late 20th century, where it -all- started and is still known for its symbolism. I'm not going to Google it all for you but here are some links. Also, I would appreciate it if you would lower your flag in percentages and not flag the troll-post for the full 100%.

2017:
http://www.oregonlive.com/portland/index.ssf/2017/11/dr_martens_portland_billboard.html

2016:
https://www.theodysseyonline.com/psa-skinhead-shoelace-code

2004:
https://www.gq.com/story/uniform-of-white-supremacy

Doc Martens threaded with white or red laces, you knew you'd likely found a white supremacist goon.

Official Hate Symbol:
https://www.adl.org/education/references/hate-symbols/boots-and-laces

Wearing such boots was and is typical of racist and non-racist skinheads alike, but racist skinheads commonly use red- or white-colored shoelaces in their boots to identify themselves as white power skinheads. It is also traditional for them to lace boots with "ladder lacing," so that the laces don't cross each other going up the boot.

To give you an idea how widespread the interest of the term 'red laces' is over the last 5 year:
https://trends.google.nl/trends/explore?date=today%205-y&q=red%20laces

To give you an idea how widespread the interest of the term 'pepe nazi' is over the last 5 years:
https://trends.google.nl/trends/explore?date=all&q=pepe%20nazi