My personal opinion is that alt-right is rising world-wide because democratic governments forgot that the way we eradicated radical ideologies post-ww2 was through making life of average person bearable. Radical ideologies can't find fertile ground among people who own their own homes, who can support whole family with a single job.
And if current solution to alt-right will be to just start wars, raise taxes and double down on policing... it will only give them more fuel.