Trying to understand another culture, without taking time to actually understand another culture, leads you to make big mistakes.
Actually no. It is standard issue Imperial Russian mayka worn by Russia's Marines, i.e. the soldiers who are attached to the Naval Fleet. Just as in the USA, Russia's Marines are an elite fighting force which is why newer special forces units also proudly wear the mayka under their jackets.
Everyone in Russia knows this and anyone who has spent time in Russia, or seriously tried to learn Russian culture, also knows this. That blue an white striped T-shirt is a symbol of manliness and is a badge of pride.
Remember who you are dealing with here. Every Russian reads the Gulag Archipelago by Aleksandr Solzhenitsyn in High School. This is a nation that has NEVER been conquered even though many nations have tried to invade. The Swedish were defeated by Aleksandr Nevsky on the outskirts of Novgorod. Napoleon and Hitler both reached Moscow, but the PEOPLE of Russia nibbled away at their forces and eventually beat them back. The story of how the Battle of Kursk was won is amazing. All the lines of defence that were put in place so the Nazis could break them, and lose some of their force in the process, until they were weak enough to begin pushing them back to Berlin
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And you could watch some of the HUNDREDS of movies and TV series about how Russians defeated the Nazis, often in small battles, scattered all over the territories west of the Volga. The most amazing heroism is portrayed in these films and TV series, and they always end by revealing that these are real people, some of whom survived the war and returned to their families.
Donbass happened in East Ukraine because that area happened to be a favorite place for Soviet Afghan veterans to retire. So most of the non-military men who rose up against the Fascists from Kiev, had fathers and grandfathers in the military.
There were even many people there who survived the Nazi occupation and who encouraged their neighbors to fight. That is why so many young fighters from Russia came to help them. This is what happens when a people has a culture of militias and collective teamwork. It's not enough to arm yourself, you have to be part of a team, like the militias in Michigan who are standing up against the police right now.