Caterpillar built the first tanks for the U.S. Military. Ford Motor Company was the first automobile manufacture to build a tank for the U.S. Military.
M1A1 Abrahms Tank.
M1a1 Abrahms
They built a tank
The first US built tank was a copy of the French Renault FT-17 or Model 1917. Less than 1,000 were ordered and built in the US in 1918. The M1917 that was constructed in the US under license, was called the "Six Ton Tank" M1917.
The US built Sherman medium tank.
After the Civil War, the US military built the frontier because of the American westward expansion.
Some built the streets and railroads. Many joined the US Military.
The Mark VIII was developed as a joint venture between the US and Great Britain, and was designed by goverment (military) designers. I do not believe that the tank itself is, or was, patented. Elements, such as catepillar style tracks, WERE patented by their creators long before tanks were first built.
M1 Abrams Tank. Mainly used by British and US forces but, this is a popular tank and is used by other military's aswell. Type 99KM Tank. This is the most powerful and heavily armoured tank in the world. Used mostly by Chinese and Russian forces.
The answer to your question is "Pentagon", the five-sided, US military headquarters built during WW2.
The first successful rockets built to go into space were ICBMs: the Soviet Sputnik I & II were launched on military ICBMs, the US Mercury spacecraft were launched on military ICBMs (Redstone & Atlas), the US Gemini spacecraft were launched on military ICBMs (Titan II). IIRC, the Delta & Saturn rockets were the first successful rockets built to go into space that didn't begin as military ICBMs. Although most Deltas are launched from Vandenberg AFB. The European Arian was the first commercial rocket built to go into space.