So Republicans don’t really care about using debt to pay for things they want. And Democrats, whose top policy wonks have been telling them that deficit fears are excessive, would surely support a program of debt-financed infrastructure spending.

In short, money isn’t why we aren’t building infrastructure. The real obstacle is that Trump, his officials, his party or all of the above don’t actually want the kind of public investment America needs. Build they won’t.

In the case of Trump administration officials, what’s striking about the various infrastructure “plans” they’ve offered — they’re more like vague sketches — is that they involve very little direct public investment. Instead, they’re schemes that would purportedly use public funds as a sweetener to induce large amounts of private investment. Why not just build stuff? Partly, perhaps, to hold down the headline cost. But such schemes would also amount to a backdoor way to privatize public assets, while possibly generating little new investment.

And while a real infrastructure plan would gain a lot of support from Democrats, an exercise in crony capitalism pretending to be about infrastructure wouldn’t.

Meanwhile, Republicans in Congress are aggressively uninterested in any kind of public investment program. During Trump’s first two years in office, they first bullied him into submitting a plan that actually provided hardly any money for new investment, then invented excuses for not dealing even with that emasculated proposal.

The truth is that modern conservatives hate the idea of any kind of new public spending, even if it would make Americans better off — or perhaps it would be more accurate to say especially if it would make Americans better off, because a successful spending program might help legitimize a positive role for government in general. And while Trump may not fully share his party’s small-government ideology, all his limited energy is going into finding ways to punish people, not help them.

So who will rebuild America? Trump and his party have had their chance, and clearly refuse to act, so it will have to be the Democrats. Their proposed Green New Deal is deliberately short on specifics, but its clear thrust is toward a revival of the American tradition of public investment in the public interest.

And my guess, which is also my hope, is that if Democrats get the opportunity — if, in 2021, they regain control of both the White House and the Senate — they won’t let funding concerns block an infrastructure push. Major health reform will need new revenue sources, but given low interest rates, debt-financed public investment would be sound policy. Build we must, build we should, and hopefully build we will.

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