Bjorn Lomborg, the one-time bete noire of climate-change activists, had a provocative op-ed in Thursday’s Post arguing that China’s “green leap forward” is a farce; the country is on track to burn massive amounts of fossil fuel, and it doesn’t use much of the green technology it produces — it exports those solar panels to places where such things benefit from heavy government support. You don’t have to agree with every one of his claims, though, to appreciate the conclusion: Ultimately, cleaning up the fossil-fuel economy will require research that makes clean-energy technologies cheaper, so that people will use it without so much government pressure. Just look, he says, at solar heaters in China — which are popular because they are cheap. Financing technological breakthroughs in energy could be one of the best investments a government can make.

This has me thinking about the debt debate. The big question on long-term deficits should be: Can the Democratic and Republican visions mix in a way that recognizes not only America's long-term fiscal problem, but also that government must have the means to do much more than simply retire the Boomers? Smart investments in things such as energy, or infrastructure, or air traffic control systems, or cancer research.

This is eminently possible, though it wouldn’t look like an ideological victory for either side.

The parties would close tax loopholes and eliminate inefficient tax expenditures, and they would raise certain taxes, too. They would do more than just nip at the edges of social spending for the retired, particularly Medicare, which threatens to totally overshadow investment in everything else in the next decade. These would enable lawmakers to maintain a discretionary budget that invests healthily in the young and entrepreneurial, instead of resigning government to financing consumption for the elderly and to servicing the debt.

Yet progressives this week are aghast that the “Gang of Six” senators currently negotiating a debt deal would dare do anything to Social Security. What’s striking is the sense of priority; the program will require reform eventually, anyway — and it’s relatively easy to fix — yet some want to run Sen. Dick Durbin (D-Ill.) out of Washington on a rail for simply entertaining the idea, even before any details are out. This alone could end bipartisan debt negotiations in the Senate. How much would some of these progressives really fight if Durbin agreed to spending plans that would end up decimating, say, the ARPA-E budget, or underfunding the repair of American highways, bridges, or water treatment plants? These are the sorts of crucial, future-oriented programs that could easily end up shafted.

Republicans, meanwhile, abhor the notion that any taxes might rise anywhere; consequently, their budget plan would continue the transformation of the federal government into little more than a big retirement plan.

Washington seems entirely too content with this fate, a fact underscored by a frustrating report Wednesday that members of both parties dislike President Obama’s best idea to check Medicare spending — an independent board of experts that would find savings when costs breached spending targets.

None of these reactions indicate that the two parties are thinking enough beyond the old politics of entitlements and taxes; Democrats bash Republicans on the former; Republicans bash Democrats on the latter. And no one ends up talking enough about developing the next solar heater.