Mitt Romney’s speech tonight was almost all about what Barack Obama hasn’t done, touching only briefly on what Romney might do if elected. That wasn’t an accident.

Romney made the obvious case against Obama: The Administration has been unable to promote economic growth, is out of ideas, and spends far too much time explaining why factors beyond its control prevented it from succeeding. This was the key pitch:

This president can ask us to be patient. This president can tell us it was someone else's fault. This president can tell us that the next four years he'll get it right. But this president cannot tell us that you are better off today than when he took office.

This is all fair enough. But Romney has yet to make a case that he would succeed where Obama has failed. The economic plan he laid out is just a rehash of the policies we had in 2007, when the economy started falling apart.

Eighty percent of the way through his speech, Romney finally got around to laying out a policy agenda. He pledged to develop domestic energy sources, promote school choice, broker trade agreements and enforce their rules, cut the deficit, reduce regulation, and repeal Obamacare.

Those are all pledges that could have as easily come from George W. Bush. Some, particularly on trade and the deficit, could also have come from Barack Obama.

Romney’s brief agenda is built on the premise, oddly popular among Republicans, that our economic stagnation was caused by budget deficits and Obamacare. It does not address the ongoing housing crisis, systemic risk that remains in the financial system, tight monetary policy, or the shortage of consumer demand that discourages cash-rich companies from expanding. The agenda has no content aimed at fixing the specific economic problems of our time.

Romney also espoused contradicting theories on job creation. He complained that Obama has failed to create jobs because “Jobs to him are about government.” But then he attacked Obama for cutting government spending on Medicare and the military -- on the grounds that doing so would cost jobs.

Romney is shallow and incoherent on policy for strategic reasons. He attacks from whichever direction is likely to be effective -- even if that means getting to the president’s left, as on Medicare -- and keeps the focus on Obama’s failures. Getting too specific might lead people to focus on Romney instead.

That strategy might be enough to win the election. But it does not help the public figure out how Romney would run the country.

(Josh Barro is lead writer for the Ticker. E-mail him and follow him on Twitter.)

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