Michael Barone‘s latest column notes that despite the president’s numerous stumbling blocks, Republicans who want his job must offer some compelling alternatives.

So it’s possible that the Republican nominee, if he or she avoids stumbles and conditions remain as they are, can win just by running against the failed policies of the Obama Democrats. But that’s not necessarily enough to govern successfully.

Republicans can argue successfully that Democratic promises of absolute security cannot be kept. Federal entitlements are, to paraphrase Margaret Thatcher, running out of other people’s money.

The problem for Republicans is that it’s impossible to foresee exactly how free-market policies will improve people’s lives. Back when Ronald Reagan was running during a similar Democratic breakdown in 1980, no one foresaw the wonders of the Internet.

The best attempt to suggest the possibilities I’ve heard here in Iowa came from [Thaddeus} McCotter, speaking at the Des Moines Register’s soapbox on the fair’s midway. “The answer,” he said, “is not to put your dreams in centralized bureaucratic Washington. The future is self-government, empowerment of the individual, a citizen-driven and more horizontal government.” We need policies that enable us to choose our own future, just as we choose our own iPod playlists and design our own Facebook pages.

That could have special appeal to young people, who voted 66 to 32 percent for Barack Obama in 2008. The hope and change he promised has turned sour, and Democrats’ welfare-state policies have proved to be more a straitjacket than they have a safety net.

Republicans are winning the argument over the Obama policies. But they aren’t yet making the strongest case for their own.