Sen. Bernie Sanders (I-Vt.) speaks to a crowd of supporters gathered June 5 outside the Walmart shareholders meeting in Rogers, Ark. (Ben Goff/Arkansas Democrat-Gazette/AP)

On Monday, after Raytheon and United Technologies announced merger plans, President Trump again weighed in on U.S. corporate business decisions, telling CNBC he was “a little concerned” about lessened competition if the defense contractor and industrial technology giant became “one big, fat, beautiful company.”

It was the latest in a long string of examples of Trump — whether by tweet or by tirade — singling out American companies: praising consumer boycotts of Harley-Davidson after a decision to move production, lashing out at General Motors for layoffs or suggesting that if consumers stopped “subscribing to AT&T, they would be forced to make big changes at CNN,” a frequent target of his media criticism.

But the president has been joined more often in recent months by 2020 Democratic presidential candidates who are also increasingly calling out companies by name, directly challenging American businesses in a way that historians and communication experts say underscores a new era.

On Tuesday, four Democratic presidential candidates — Sens. Bernie Sanders (I-Vt.), Elizabeth Warren (Mass.), Kamala D. Harris (Calif.) and Amy Klobuchar (Minn.) — signed a letter calling on McDonald’s to require all franchise stores to update their policies on sexual harassment. Several others have also joined in coordinated protests with McDonald’s employees.

Just in time for Facebook’s shareholder meeting May 30, Warren, who has specifically called for the breakup of tech firms such as Facebook and Google, put up a billboard in San Francisco reading “Break Up Big Tech.”

And on June 5, Sanders attended the Walmart shareholder meeting to present a proposal calling for worker representation on the retailer’s board, a move that followed his “Stop Walmart Act,” a bill to curtail stock buybacks unless companies meet wage and benefit standards.

He has also proposed a “Stop BEZOS Act,” a dig at Amazon CEO and Washington Post owner Jeff Bezos, aimed at making large employers pay for employees’ use of social safety net programs. Even 2020 front-runner Joe Biden mentioned the online behemoth by name this past week, saying Tuesday at a campaign stop that “I have nothing against Amazon but they should pay a few taxes,” according to tweets from reporters.

Amazon declined to comment. McDonald’s said in a statement it “has always had an unyielding commitment to providing a safe and respectful work environment for all” and pointed to another statement by the National Franchise Leadership Alliance.

There are certainly other examples of presidents calling out American companies — Teddy Roosevelt set out to break up monopolies such as Standard Oil; John F. Kennedy had a standoff with U.S. Steel; and Barack Obama publicly shamed Staples about wages and health insurance, to name a few.

But experts say the increasing frequency and normalization with which politicians single out American enterprises, often to make a political point, represent a notable break from tradition.

“Usually when politicians attack, they attack a sector so they’re not talking about specific companies — it’s ‘Wall Street’ or ‘Silicon Valley,’” said Julian Zelizer, a political historian at Princeton University. “What you’re seeing now is a proliferation of politicians highlighting specific companies, and it seems to be opening up a new way politicians can threaten or lash out.”

Look at the papers of any post-World War II president, said Larry Jacobs, a professor of political studies at the University of Minnesota, and there’s a long trail of chatty, clubby letters between the White House and business leaders that depict a deep, symbiotic relationship.

Yet there’s a dissonance between that history and today’s rhetoric that “feels like a new era,” Jacobs said. “The president — and now Democratic front-runners — going after individual businesses is an even sharper signal that the post-WWII era of a business-government marriage is fraying.”

There are a host of reasons for the shift. One is that Trump is unlike presidents before him and has broken expected norms — by inserting himself into the news cycle, he turns business stories into news about him while signaling to voters he is working to retain jobs or reduce prices.

But the trend is not all the result of Trump, experts say. In a crowded Democratic field, a world of ubiquitous social media and expanded income inequality, candidates have to do more to stand out, and voters are looking for accountability. “When everybody’s got a voice about everything, that voice has to get pretty loud and obstreperous to be heard,” said Nancy Koehn, a historian at Harvard Business School.

On the left, in-depth policies regarding taxes on the wealthy or worker representation on corporate boards don’t always pass the proverbial “bumper sticker test.” As a result, some believe direct critiques of companies are a shorthand way to make concepts more accessible. “Corporate name dropping is the flashing lure to catch attention and attach a snippet of a proposal,” Jacobs said.

In addition, a shift in fundraising tactics toward Internet campaigns that bring in piles of small contributions relies on provocative messages that motivate people to give. “Now those one-off critiques of individual companies, if they are properly targeted, have a political currency,” said Bruce Haynes, vice chair of Sard Verbinnen’s public affairs office in Washington.

Some suggest companies’ own actions have prompted the more direct critiques. Brad Todd, a Republican media consultant and co-author of a book about populism, said in a text message there were more “national brands that were associated with national pride” before the rise of multinational corporations. “In 1984, every American knew Budweiser and Levi’s were as American as apple pie because those companies sought to project that.”

Communications experts advised companies not to get into Twitter wars, to be responsive but not respond in kind, and to prioritize connecting with White House or legislative staffers early on when making announcements that could come under fire. In most cases, companies should use the opportunity to explain their story or strategy again rather than fight.

“Don’t escalate, don’t shoot back,” said Davia Temin, a communications and management coach on reputation issues. “The last thing an awful lot of people want is a one-upmanship match between the president or presidential candidates and an individual company.”

Damage, experts say, is often fleeting. Some analyses have shown that hits to stock prices after a Trump tweet are temporary. And after years of Trump’s Twitter attacks, companies appear to fear them less, proceeding with their plans while opening dialogues with the president or candidates about their decisions.

After Trump’s comments Monday, United Technologies Chairman and CEO Greg Hayes told CNBC the companies had “no overlap” and that he was “looking forward to talking to the President later” that day, saying, “I think he’s going to be supportive as he has been for both of the companies over his administration.”

Before its shareholder meeting, Walmart said in a statement that “if Senator Sanders attends, we hope he will approach his visit not as a campaign stop, but as a constructive opportunity to learn about the many ways we’re working to provide increased economic opportunity, mobility and benefits to our associates.” Then at the meeting, CEO Doug McMillon thanked Sanders for attending, called for Congress to raise the minimum wage and spent part of his remarks talking about employee initiatives.

A restrained response of watching and listening is usually best, said Leslie Gaines-Ross, chief reputation strategist for Weber Shandwick. “I don’t know that I could name an incident where a company has been mentioned by a politician and suffered lasting damage,” she said. “Companies suffer when they have a real crisis — a product recall, a leadership transition, some kind of malfeasance. Those are what turn into real crises you can measure with shareholder losses.”

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