Mencken was a typical intellectual elitist!  Just like Woodrow Wilson, he was also a progressive and a racist--believing that self-determination was only for WASPS and that keeping black slaves was not only morally acceptable, but necessary to preserve the plantation economy.  The Union soldiers died for self-determination for all.  The modern democrats of both south and north haven't changed their stripes since--keep them poor and ignorant--and therefore dependent--and they'll keep voting for you!