That would be the logical thing to do, but history intervened. It was called World War 2.

The federal debt really started to grow with the New Deal, so not only was Roosevelt putting unemployed labor back to work, but unemployed capital as well. Then everyone started buying war bonds with their savings and it became the patriotic thing to do. The war gave a large booost to technological innovation, becoming the heart of the industrial and tech boom following it.

Then it started to weaken by the Vietman War, which along with Great Society programs, began to be funded with loose money, causing the break with the gold standard, so then money became largely oil based and debt backed.

Volcker couldn't have cured stagflation with higher interest rates, as that squeezed the flow of money to those willing to borrow and grow the economy, houses, businesses, etc, while gifting higher rates to those already sitting on more than they needed. What cured it was Reaganomics

. When the Fed raises interest rates, one method is to sell the debt borrowed to create the money in the first place, so the only difference with the treasury issuing new debt is this money can be spent back into the economy, not retired.

Naturally the government can spend it on things the private sector would never invest in, so there isn't the competition for investment potential, like warfare and welfare.

The fact is that many of our social programs are not designed to build stronger communities, but to keep people wards of the state and cheap labor for corporations. When Reagan tried to cut it in 86, on of the main lobbyists against cutting welfare was Archer Daniels Midland, the large food conglomorate, as the money shortly ended up in their pockets, with the people as just a pass through.

Further;

https://medium.com/dialogue-and-discourse/the-worm-in-the-apple-of-modern-capitalism-a46081000d5a