The 747 only exists because of subsidies and defense contracts. If the US government were not heavily involved in the industry, we'd all be flying in Airbus jets.
These subsidies made the development of the 747 possible.
Look at the history of Boeing [1]. It's all government contracts, with the technologies and designs developed for them being re-used in their commercial offerings.
Without cost-plus contracting paying for cutting-edge R&D, they would have been about as capable of building airplanes as I am, in my garage. Their entire business is built on millions of hours of engineering experience in building planes for the military, applied to the commercial sector.
> It's all government contracts ... Their entire business
That's not what your source says at all. Boeing, for example, developed the first modern airliner in the 1930's. Pretty much all airliners derive from that. In fact, you can reasonably argue the other way - Boeing's military designs derived from their airliners. This is certainly the case for the B-17 and the KC-135.
Please identify the military technology and subsidy in the 747, and where the money came from to build the Everett plant.
The money came from corporate debt which was on very favorable terms because of the government cash flow for military contracts. The other part came from investors who invested into Boeing because of growing stock prices due to military contracts.