Why Do African Americans Vote For Democrats?

Let us “unpack” this

O. J. Rapp — http://lbjlibrary.org/collections/photo-archive/photolab-detail.html?id=1107 — President Lyndon B. Johnson signs the Civil Rights Act of 1964

Every election season, the debate begins — why do Democrats loyally vote for the Democrats even though the Democrats do nothing for them?

(Full Disclosure: I am not a Democrat. And Full Disclaimer: I am not endorsing anyone to vote for Democrats or Republicans, just vote)