Discussing one of the four major priorities identified in Business Roundtable's new "Invested in America: A Growth Agenda for the U.S. Economy," BRT Chairman Randall Stephenson appeared on CNBC's The Kudlow Report on Thursday and affirmed the economic imperative of tax reform. (Story and video here.)

The other priorities identified in the growth agenda are restoring fiscal stability, fixing America's broken immigration system, and expanding trade, starting with passage of Trade Promotion Authority.

Transcript of a portion of the Kudlow interview with AT&T Chairman and CEO Stephenson:

Randall Stephenson: As I make the rounds in Washington, there are a lot of competing ideas about what we need to do to get the economy growing. But I will tell you it comes down to one basic simple equation, and that is, if corporate America is not investing, they're not hiring, and we’re not growing.

It's not a coincidence that private investment as a percent of GDP is at its lowest level since World War II. So if we want to get America growing, we have to get corporate America investing again. The ideas that we laid out in the Wall Street Journal are those things that we think are most relevant and could get America investing and growing again in the quickest way.

Larry Kudlow: Well, once again I agree, I mean, particularly your point about private business investment. You're absolutely right, as a share of the economy. I think if you adjust it, it’s actually lower in level today than it was back in 2000…

But here again is my problem. The administration, the president sometimes talks about tax reform, but he wants it to be revenue-positive. This gets muddled up in the whole issue. He wants a 28 percent marginal tax rate, sometimes, when he talks about it, but he wants to close loopholes so he will net out money for his spending plans. That's point number one.

Point number two, something you mentioned in your piece, profits that are overseas, Mr. Obama wants a rather heavy penalty tax on them. Again, you appear to be at loggerheads with his policies.

Stephenson: Well, again there are a lot of proposals on how to do tax reform in Washington, D.C. I would at least like to just get us talking about what is the right tax structure. And I would suggest to you bringing preferences down, eliminating a lot of preferences in exchange for a lower rate IS the right recipe. Because as you get the rate lower, then the incremental returns on investment are that much higher.

And at the end of the day the U.S.  tax rates are at a completely uncompetitive level with the rest of the world. And make no mistake about it: Capital markets today are very liquid. They’re very, very free. Capital is flowing like water today. If we have tax rates that are too high, the capital will not flow here, it will flow to competitive alternatives in other countries.