Chris Edwards has a great piece on Cato-at-Liberty attacking former White House adviser Christina Romer’s Keynesian economics. Her assertion that “government spending on things like basic scientific research, education and infrastructure . . . helps increase future productivity” gets the full treatment:

• "Most federal spending is on transfers and consumption, not investment. The debt crisis we face is driven mainly by entitlements, which is consumption spending. Romer’s talk of investment spending is a rhetorical bait-and-switch.
• "Romer doesn’t distinguish between average and marginal spending. If some federal investment spending has created positive net returns, that doesn’t mean that additional spending would. Governments already spend massive amounts on education, for example, so the marginal return from added spending is probably very low.
• "If the government investments that Romer touts are so valuable, then why hasn’t the government done them already? After all, federal, state, and local governments in this country already spend 41 percent of GDP.
• "If science, education, and infrastructure investments have the high returns that Romer seems to think they do, then why does the government need to be involved? Private firms seeking higher profits would be all over such investments.
• "Romer mentions that the “social returns” on some investments might be higher than purely private returns. However, that doesn’t mean that the government should automatically intervene. For one thing, the government suffers from all kinds of management failures and other pathologies.
• "Romer also ignores that the government imposes substantial deadweight losses on the economy when it commandeers the resources it needs for its 'investments.'"