Patriotism is best exemplified through auto-critique. When you're willing to stand up within the group and say 'It is wrong for Black people to be anti-Semitic ' or 'It is wrong for America to discriminate against persons of African descent and made them slaves and based its wealth upon free labor ' it's crucial to say that.
The cause of justice is the cause of humanity. Its advocates should overflow with universal good will. We should love this cause for it conduces to the general happiness of mankind.