Man, if only interest rates were at historic lows and there were millions of unemployed people, we could borrow the money cheaply and hire the people easily to rebuild our infrastructure! Oh well...
Hush, little padawan. If the government borrowed to invest in infrastructure, education or anything else, it would divert badly needed capital and employees from the private sector where they are being used to the max already. This is called the "crowding out" effect. There's nothing to spare!
Again, You don't understand how markets operate on the
margins not based on available stock(stock as in quantity, I'm not referring to equities).