I don’t recall a time when more people were running for president and fewer of them offered anything more than poll-tested generalities designed to rally their own bases. No one surprises you with any daring. If we could tax their cliches, we’d balance the budget.

The defeat by House Democrats — with an assist from hard-right House Republicans and praise from Hillary Clinton — of President Obama’s sensible plan to expand Pacific free trade and pair it with worker and environmental protections was a bad sign that many more Democrats are now polarizing toward the populist left. Since the Republicans have already purged their moderates, this trend does not bode well for the country. It means that the hybrid/centrist blends that on many issues can create the most resilient solutions are “off the table.” As long as that’s the case, there is little chance you will pass on the American dream to your kids.

Just go down the list. With interest rates this low, Washington should be borrowing billions to invest in infrastructure — roads, ports, airports and 21st-century connectivity and both medical and basic science research — to make us more productive and create jobs. And we should be pairing that with phased-in entitlement trims and means-testing to Social Security and Medicare to make sure that these safety nets, as well as discretionary spending on education and research, will be there for the next generation.

Given the knowledge age we are in, it is crazy that we are educating the world’s brightest kids in our colleges and then sending them home. We should be giving green cards to every high-I.Q. risk-taker who wants to work in America, as well as the energetic less-skilled immigrants. Yes, it must be done legally, with a plan and tight borders. We need a high wall — but with a very big gate. Look at how many start-ups today are led by recent immigrants.

Given the incredible power that new technologies give both governments and terrorists we need a strong American Civil Liberties Union and a strong National Security Agency. In a cyberage, you should want an A.C.L.U. watching the watchers. But you should also want an N.S.A. watching the superempowered, cyberempowered angry people. Civil liberties absolutists may think the 9/11 era is over, but do the jihadist fanatics who use Facebook, Twitter and WhatsApp as their command and control system? We need to worry about Big Terrorist and Big Criminal as much as Big Brother if we want to prevent another 9/11.

How is it that we are not deploying a carbon tax and using that to reduce payroll taxes that discourage hiring and shrink corporate taxes that reduce investment? Many economists — left, right and center — agree that a carbon tax, with adjustments for low-income earners, makes a world of sense. How is it that our two parties cannot agree on imaginative solutions to ease the burden of $1.2 trillion in outstanding student loans — by, say, enabling graduates to pay off student loans with pretax income, the same way we allow workers to save in 401(k)s? The Highway Trust Fund, the primary source of financing for roads and mass transit is going broke primarily because House Republicans won’t agree to an increase in the federal gasoline tax, which has not been raised since 1993!

Finally, now that Obamacare is the law of the land, Republicans should be joining Democrats to strengthen it and expand its tools to cut medical costs — rather than keep trying to kill a market-based health care solution that was originally a Republican idea.

Partisanship is vital to a healthy democracy — but not when it becomes an end itself, just an engine for politicians to raise more money to win more elections to raise more money — without ever daring to stop and challenge their own base when necessary. In Silicon Valley, collaboration is how you build great products with others. In Washington, it’s how you destroy your career. In cars and crops, hybrids are the most resilient solutions; in politics today, they’re toxic. Eventually that will sap our strength.

I like the way Clive Crook, a Bloomberg View columnist, puts it: “Can any self-respecting political thinker any longer be a centrist? I’d say so. For me, the question is how any self-respecting political thinker can be anything else.” How can you have a serious public policy discussion without acknowledging trade-offs? Crook asked. “True believers of right and left organize their ideas around the hope that there aren’t any. For progressives, ‘fairness’ trumps everything; for conservatives, ‘freedom.’ Balancing either against anything else is a moral violation — but, as luck would have it, the need never arises. If you’re a progressive, you can raise tax rates without discouraging effort, and mandate higher wages without reducing the demand for labor. If you’re a conservative, you can cut taxes without harming essential public services, and roll back regulation without putting anybody at risk. If centrists didn’t always try to be polite, I’d call this aversion to trade-offs infantile.”

Centrism, noted Crook, isn’t automatically good or bad. It can be “pointless and productive, lazy and energetic, timid and brave.” At its best, it may rarely inspire, but, at its best, it has a lot better chance of prolonging the American dream than either party alone.