KRISTOF: The secret weapon: All of us

To pound that message, Republicans turned to a Delaware businesswoman, Sher Valenzuela, who is also a candidate for lieutenant governor. Valenzuela and her husband built an upholstery business that now employs dozens of workers. Valenzuela presumably was picked to speak so that she could thunder at Obama for disdaining capitalism.

Oops. It turns out that Valenzuela relied not only on her entrepreneurial skills but also on — yes, government help.

Media Matters for America, a liberal watchdog group, documented $2 million in loans from the Small Business Administration for Valenzuela’s company, plus $15 million in government contracts (mostly noncompetitive ones). In a presentation earlier this year, Valenzuela described government assistance as an entrepreneur’s “biggest ‘secret weapon.’” Someone has set up a parody website, using the name of Valenzuela’s company, First State Manufacturing, to mock the Republican message. The site, FirstStateManufacturing.com, declares, “Thank God government was there for me.”

In short, the Republicans are inadvertently underscoring the point that Obama was expressing in his “you didn’t build that” comment in July. Obama noted then that “if you’ve been successful, you didn’t get there on your own.” He pointed to public investments in roads and bridges that enable businesses to flourish, and then he inelegantly added, “If you’ve got a business, you didn’t build that.”

Fox News erupted in outrage, selectively editing the clip to confirm Republican prejudices that Obama doesn’t understand the private sector. This fits into the Republican narrative that business executives are heroic job creators when they aren’t held back by regulations and taxes imposed by quasi-socialist Muslims born in Kenya. Democrats tried to highlight a flaw in that narrative when they released a new ad pointing to Mitt Romney’s outsourcing of jobs and telling him, “You didn’t build that — you destroyed it.”

Yet to me, that Democratic line of attack on Romney as a serial job destroyer feels unfair. Sometimes the way to save a company is to cut labor costs or outsource jobs, and almost nobody wants to ban trade or overseas production even though they can cost jobs.

What is fair is to observe that the Republicans’ claim that they are the great job creators is a fiction.

Robert S. McElvaine of Millsaps College examined employment data for the 64 years from the beginning of Harry Truman’s presidency to the end of George W. Bush’s. He found that an average of 2 million jobs were created per year when a Democrat was president, compared with 1 million annually when a Republican was president.

More pointedly, and unfortunately for Romney, business executives have only a mediocre record when transferring their skills to government. In the last great economic mess, this country was led by a Republican who had been stunningly successful in business: Herbert Hoover. Hmm. More recently, President George W. Bush staffed his cabinet with CEOs who had been stellar in the private sector — and that didn’t work out so well, either.

Obama’s point about our shared undertaking was made last year, more eloquently, by Elizabeth Warren, the Massachusetts Democrat running for Senate: “There is nobody in this country who got rich on his own — nobody!” she said. “You built a factory out there? Good for you. But I want to be clear: You moved your goods to market on the roads the rest of us paid for; you hired workers the rest of us paid to educate; you all were safe in your factory because of police forces and fire forces that the rest of us paid for. ... You built a factory, and it turned into something terrific or a great idea? God bless. Keep a big hunk of it. But part of the underlying social contract is, you take a hunk of that and pay forward for the next kid who comes along.”

In short, taxes don’t just smother. They can also fuel growth — when they’re invested in highways or the Internet, in colleges or early childhood education. They can create opportunities, as they did for Sher Valenzuela.

Or for Romney himself. He built his Bain empire partly because he was smart and hard-working, but also because of a great education and because of tax breaks for debt financing. Tax loopholes helped him build his fortune, and other loopholes gave him the low tax rates to retain it.

If the Republican convention wishes to highlight and explain Romney’s success, it should have a moment of silence to honor our infernal tax code.

Who built this country? Entrepreneurs, yes. But so did schoolteachers and railway construction workers. Doctors and truckers. Scientists and soldiers. You didn’t build it, Mitt Romney — we all built it.

Nicholas D. Kristof is a columnist for the New York Times.