I seriously doubt that any of these alt-right people truly believe that they will ever get the all-white utopia they claim to want, and they’ll never be able to achieve everybody of color and/or against their crazy agenda to leave the country. Only the most deluded of their number believe this objective is within reach.
So what do they expect from a Trump presidency? A Trump presidency lends legitimacy to their cause, as did the Trump campaign. They now don’t have to operate underground on the fringes — they can be more overt in their propaganda. They will get more money and more followers, strengthening their movement. And this will give them a greater voice in Washington. Which they hope will ultimately result in the chipping away of laws that prevent discrimination, laws that protect minorities, etc.
This is an achievable goal, and one we should vigilant about preventing.