How do you feel about his cause?
As far as I know and I don't trust media. It is a demostration about freedom of speech and defending the minority against their rights being suppressed. I say stand and fight for the rights that our founding fathers fought for because those same suppressed rights were in their homelands too.
How do you feel about him and other players kneeling during the national anthem?
I honestly do not feel offended by a person or people taking a knee during the national anthem as to me that is a deeper sign of respect up to laying prone before your deity. Again I do not trust the media so I take what little I watch or hear with a grain of salt.