Keynesian economics — which dominated economic thought for a decent chunk of last century — said yes. Other schools of economic thought — which I find more plausible — do not think so. Gregory Mankiw had a good, brief discussion in the NY Times last month of how there is ample reason to doubt that increased government spending is what the economy needs.
Also of note: At the end of the article, Mankiw gives this quote from Paul Samuelson: “I don’t care who writes a nation’s laws or crafts its advanced treaties, if I can write its economics textbooks.” That’s worth pondering in the event that we ever doubt the importance of sound economic theory.