I'd say that a version of the fallacy of division is at work :
A is a part of B
B has property X
Therefore A has property X.
In the Bernie Saunders example :
1 Bernie Saunders supports the government (A supports B)
2 The government is fundamentally white supremacist (B has property X = is white supremacist).
3 Therefore Bernie Saunders supports white supremacy (A has property X = is white supremacist).
One thing that's wrong here is that if Bernie Saunders supports the government this does not entail that he supports all its policies; he may support all of them but supporting the government only need entail supporting some of its policies. Whiter supremacist policies need not be among the policies Bernie Saunders (specifically) supports when he (generally) supports the government. Compare : a Republican might support Donald Trump's administration without supporting its treatment of illegal Mexican immigrants or its tariff policy.
Also there is the possibility that even if BS supports all the government's policies he does not realise that some of them, even the fundamental ones, are white supremacist. In this case it would be only a half-truth to say that he supports white supremacy : his actions de facto support it but he does not know this and he does not accept a white supremacist agenda intentionally since white supremacy has no place in his value system.
I realise this only tackles one of your examples but you did offer a set of 'or's.