Umm...dude...you are comparing apples with oranges while thinking they are peaches.
I'm not sure how you can possibly think scientists, paid a wage, can possibly buy all the land required, pay for and build the trillions of dollars worth of facilities, pay for all the staff required every year, etc . The scientists you referred to, on a project to build two small items (compared to what you are suggesting), were utterly backed up by government, without whom, they could do nothing.
by mid-1942 it was obvious that a vast array of pilot plants, laboratories, and manufacturing facilities would have to be constructed by the U.S. Army Corps of Engineers so that the assembled scientists could carry out their mission
It was government that coordinated their efforts across international borders. Ie it is very obvious that your suggestion requires international political
In the fall of 1941 Harold C. Urey and Pegram visited England to attempt to set up a cooperative effort, and by 1943 a combined policy committee with Great Britain and Canada was established. In that year a number of scientists of those countries moved to the United States to join the project there.
Scientists who also engineer things do so at the small scale (which still requires funding by someone else). The large scale requires funds, facilities, materials that must be paid for by government/corporations that can afford such things:
Several physical methods to do this were intensively explored, and two were chosen—the electromagnetic process developed at the University of California, Berkeley, under Ernest Orlando Lawrence and the diffusion process developed under Urey at Columbia University. Both of these processes, and particularly the diffusion method, required large, complex facilities and huge amounts of electric power to produce even small amounts of separated uranium-235.
And each linked
example you provided , the actual engineering/execution parts are left to government/corporations with deep pockets. The other examples you provided, after the initial discovery, were also taken over by business / corporations etc. Ie. the scientists made the discovery, the worldwide implementation was done by others.
Governments do diddly squat
Governments purpose has always been order, and facilitation. Order by its very nature means records/restrictions/judements/defence. Facilitation by its very nature is indirect. You want corporations to build these things...government provide incentives to corporations to carry out projects that would otherwise be economically unsound for them to carry out.
No where in here, at all, do scientists have the power to do what you are suggesting. The money side alone makes it impossible. Scientists aren't going to be able (or willing) to pay out of their wages for trillion dollar solutions. Impossibility aside - to imply they do so is patently unjust (everyone should have to pay for it).
Moving on from the finance impossibility, the engineering scale is so astranomical that even you should be able to see how ludicrous the suggestion is to say that soft, deskbound scientists shold leave their workplaces by the hundreds of thousands to suddenly work as:
- welders, scrapers, concreters, electricians, fitters and turners, plumbers, civil engineers, architects, estimators, accountants, lawyers (contracts), logistics, administration (payroll, front office etc),....etc
It's good to want global warming solved. It's not helpful to yourself - to not think through how something would actually be carried out.