> There's a huge to-do list of jobs that need to be done at almost every level, from design and build of significant infrastructure in most countries around the world, to community-level support work.

Infrastructure overinvestment is extremely destructive to the environment, and at least in Japan and China has led to economic problems:

https://www.theguardian.com/world/1999/jul/27/jonathanwatts

http://www.slate.com/articles/business/project_syndicate/201...

Public policy should be focusing on ways to scale down infrastructure and reduce population.

> It would be perfectly possible to retrain the long term unemployed for all but the most difficult design and management elements.

Job training is one of those Reaganisms that has proven not to work in a capitalist economy: http://www.cornellpress.cornell.edu/book/?GCOI=8014010004030...