Where we differ is that I don't see Obama as the bad guy you do. Unity is the goal, sure, but what "white" conservative America doesn't seem to like is pointing out the bias and the system(s) that exist because of that bias. That's the status quo. That bias is wrong. If The devisiveness is coming from the Left, Obama, and even more so Sanders challenging that bias then so be it. The fact that people are up in arms because equality across the board is being sought, that's a problem.
Basically.
Conservative whites are in their feelings. Have been since the black man with a funny name got into office. They feel like they're "losing the country" to minorities.
Why do you think Trump started his campaign off with building a wall? Hispanics are the fastest growing demographic in this country. What better way to appeal to bigoted, poor whites them to tell em "Hey, we're gonna make sure we keep all them Mexicans out". For real, Trump's campaign started back when he was questioning if Obama was born in America and if he was Muslim.
Fact is, poor white America is scared
They're scared that minorities will soon become majority, they're scared that their mortality rate is increasing while everyone else's is decreasing and they're scared because America has proven they'll not only vote in a minority for President but even give him a second term.
Trump taps into all their fears. That's why he's in the lead. Not because of policies, not because of experience, but because he's promising to "make America great again". Which means "make America white again".