Now, with the imminent nominations of Donald J. Trump and Hillary Clinton as the respective Republican and Democratic candidates for president, it’s fair to say the Business Roundtable is fit to be tied.

“There’s a great sense of frustration here,” John Engler, the group’s president and a former Republican governor of Michigan, told me this week. “We’re now faced with two candidates who, when it comes to the United States economy, have diametrically opposite viewpoints from us. It’s cause for great concern.”

That a Democratic candidate might diverge from the group’s pro-business agenda is no surprise, but Mr. Trump’s embrace of economic policies that are anathema to its members is seen as a betrayal of bedrock Republican principles.

In a fiery anti-free-trade speech last month, Mr. Trump said he would “rip up” existing free trade agreements, including the North American Free Trade Agreement. He wants to brand China a currency manipulator and impose a wide array of “taxes and tariffs” to protect American workers.

“We’re just on the opposite side of Trump on trade and immigration,” Mr. Engler said. “Everything has been upended.”

If anything, Mrs. Clinton seems more closely aligned with the business group than Mr. Trump. Although she now opposes the Trans-Pacific Partnership trade deal she supported as secretary of state, “Fundamentally, she and her husband come from a free trade perspective,” said Gregory Mankiw, professor of economics at Harvard and chairman of the Council of Economic Advisers under President George W. Bush. “It’s hard to believe in her heart of hearts she’s opposed to free trade. And in general, she’s more aligned with mainstream economic thought.”

The Business Roundtable has been officially nonpartisan since its founding in 1972, and it does not endorse any candidate for political office. But it has long been courted by leaders of both parties. President Obama has met with the group on multiple occasions. Its members include the chief executivesof American Express, FedEx and Walmart, and the organization’s advocacy of large corporate interests and what it considers pro-growth economic policies has usually aligned it with Republican orthodoxy.

Mitt Romney, a former Republican presidential candidate, was warmly received when he met with the group in 2012, and, as a founder of private equity firm Bain Capital, he was on a first-name basis with most of its members. Mr. Trump does not have the same standing.

“It’s surprising to me that Trump doesn’t know many of our members and they don’t know him,” Mr. Engler said. “Romney knew almost everyone.”

Mr. Trump and his campaign staff did not respond to requests for comment.

Although not going quite as far as Mr. Trump in repudiating existing free trade deals, the Republican Party largely embraced his protectionistphilosophy this week, declaring in its draft party platform that all trade deals should “put America first.” In sharp contrast, the Business Roundtable says on its website, “Open markets for international trade and investment are essential for supporting U.S. economic growth and jobs.”

The business group’s support for free trade has widespread bipartisan support among economists. Mr. Trump’s positions “show a complete lack of understanding of international trade,” said Alan S. Blinder, a professor of economics at Princeton, a former economics adviser to President Clinton and a former vice chairman of the Federal Reserve. “Throwing up barriers doesn’t work. It will raise the exchange rate, which will hurt exports and push the deficit up. Barriers may help a favored few, but at the expense of everyone else.”

Professor Mankiw agreed. “There are few things economists are unanimous about, but support of free trade comes pretty close. There are good reasons for international specialization, and by and large Americans have benefited tremendously. Do we really want to produce T-shirts here and pay $60 for something that now costs $15?”

He acknowledged, “Technological progress has displaced many manufacturing jobs. That raises productivity, which is the main driver of a better standard of living. But economic change is rarely good for everyone. In the short term, workers lose their jobs, and that’s hard. There are winners and losers, and Trump is tapping into the losers.”

On immigration, the Business Roundtable argues for expanded legal immigration, especially for highly educated and skilled workers: “America has a long history of welcoming immigrants who through their own drive and hard work contribute to our society and economy,” its website says.

“It makes no sense to bring the best students to our graduate schools and then force them to go home,” Mr. Engler added. “We don’t do that with athletes. We get the best in the world. We should be doing that for engineers.”

Mr. Trump has occasionally expressed similar sentiments, but he ridiculed a bipartisan effort to expand a visa program that allows international students who complete advanced degrees to remain in the United States, calling Marco Rubio, one of the bill’s sponsors, “Mark Zuckerberg’s personal senator.” And more broadly, he has called for curbing immigration and deporting the estimated 11 million illegal immigrants residing and working here.

“The xenophobia of Trump supporters isn’t really economic,” Professor Mankiw said. “It’s cultural. They don’t want people here speaking foreign languages.”

Although no one, including the Roundtable, supports illegal immigration, many economists fear the potential economic disruption of deporting millions of people. “Where are you going to find the millions of workers to replace these people?” Professor Blinder asked. “And that’s without even touching on the humanitarian aspects.”

Probably no issue has more closely united business interests and Republicans over the years than tax policy, although even most Democrats and the Obama administration agree that it is in urgent need of change.

The Roundtable says “America needs a modern tax system. Key components of business tax reform include: setting the corporate tax rate at 25 percent; adopting a modern international tax system; and making U.S. tax policy permanent.”

Mr. Trump goes further: He would lower the corporate tax rate (now 35 percent, the highest in the developed world) to a flat 15 percent while cutting corporate loopholes.

That, for the Roundtable and many others who favor tax overhaul, goes too far. The Tax Policy Center of the Brookings Institution estimated that Mr. Trump’s tax proposals taken together would reduce federal tax revenue by $9.5 trillion over the first decade and increase the national debt 80 percent by 2036.

“We proposed 25 percent because we felt we had to suggest something fiscally sustainable,” Mr. Engler said. “We thought we made a reasonable proposal that could thread a bipartisan needle. You can get to 25 percent without blowing a hole in the budget.”

Mr. Trump will no doubt get an earful if he accepts the business group’s pending invitation to meet in an off-the-record session in September. (The group has invited Mrs. Clinton as well.) Neither candidate has accepted, but both have said that they are interested, according to Mr. Engler.

Of course, a cool reception from the Roundtable may be just what Mr. Trump wants, given that he is campaigning against “elites.” He has alreadybrushed off similar criticism from the United States Chamber of Commerce, saying the group is in the grip of special interests and “controlled totally by various groups of people that don’t care about you whatsoever.”

Indeed, Mr. Trump could have had Roundtable members in mind when he lumped together “powerful corporations, media elites and political dynasties” as “the people who rigged the system,” as he put it in a speech this month.

“I want you to imagine how much better our future can be if we declare independence from the elites who’ve led us to one financial and foreign policy disaster after another,” he told cheering supporters.

 **More:

http://www.nytimes.com/2016/07/15/business/for-trump-business-leaders-are-more-elites-to-resist.html?_r=1