GDP = C + G + I + NX
"C" is equal to all private consumption, or consumer spending, in a nation's economy
"G" is the sum of government spending
"I" is the sum of all the country's businesses spending on capital
"NX" is the nation's total net exports, calculated as total exports minus total imports. (NX = Exports - Imports)
My overall point is that the economy is highly dependent upon government investments, like roads, bridges, etc., but also the mechanics of government. Because I don't have to worry that my food, drugs and the airplane that I travel on are safe -- because a government inspector took care of that, I can focus on what I do. That makes an economy much more efficient.
150 years ago, the government built canals that the private sector wouldn't build. That increased commerce and expansion in marvelous ways that certainly did contribute to economic activity. The same is true for the interstate highway system. To deny that government helps the economy is merely ideological blindness.
Yes, I know that right-wingers cling to the faith like a religion that the government doesn't do anything good, just takes money and does nothing with it but even the most rudimentary review reveals that view is nonsense.