I don't think the USSR is the best example of a constitution protecting the rights and freedoms of the people.

> Citizens of the USSR of different races and nationalities have equal rights

This rings pretty hollow when you look at the history of Russification. And no doubt this clause is in the constitution because of the Russification policies of the Russian Empire, yet that didn't stop the Soviet Union from doing very much the same thing. https://en.wikipedia.org/wiki/Russification