When Representative John Mica, a Republican from Florida and chair of the House Transportation Committee released his proposal for the overdue Surface Transportation Reauthorization bill earlier this month, liberals condemned the plan's lack of investment in infrastructure. They missed, however, a bigger failing: Transportation spending is not just underfunded in this country; it's broken, and we can't afford to wait another six years to fix it. House Republicans, though, haven't proposed sensible transportation policy changes, even ones conservatives should support. Smart-growth advocates, unions, and environmentalists had been excited by President Barack Obama's $556 billion proposal for the six-year transportation bill, but Mica's plan offers a mere $230 billion because Republicans are unwilling to raise the gasoline tax, which pays for federal transportation spending. They are also unwilling to create new sources of funding such as a tax on vehicle miles traveled (this would be...