This nice Reason article talks about how Obama wanting to "create" 5 million green jobs really means 5 million jobs will be transferred from something else. If green jobs are less productive than non-green jobs, it is akin to the
Broken Window Fallacy. Nice job, Reason, I haven't thought of it like that.
In the long-run, the supply of jobs is perfectly inelastic. You cannot change the number of jobs, only the allocation of jobs across sectors.