As the U.S. inflation rate ramps up, obvious to many people at the grocery store and the gasoline pump, President Joe Biden has asked the Federal Trade Commission and the Justice Department to investigate whether the exercise of market power by major corporations (“Big Food” and “Big Oil”) is responsible for the fastest commodity price increases in two decades.

Before inflation began rearing its ugly head, Washington’s trustbusters and some states’ attorneys general were more apprehensive about Big Tech, worries that may crystallize soon in opposition to Microsoft Corp.’s proposed $75 billion acquisition of video game giant Activision, the company’s first major step into the “metaverse.”

Renewed antitrust activism is one fruit of Biden’s first year in the White House. The administration apparently has set itself on a course back to the big-is-bad law enforcement agenda of the 1950s through 1970s, when a business’s sheer size was enough to put it in the crosshairs of the Sherman, Clayton and FTC acts, passed more than a century ago, ostensibly to attack monopolies—a too-much overused term—thereby aiming to preserve competitive market conditions.

Enforcing the antitrust laws in practice first requires defining a market that is dominated by one or more companies and, second, showing that consumers in fact have been harmed by the powers over prices and product features exercised by the sellers in that market.

Antitrust policy makes no sense if a consumer-welfare standard is abandoned, as some commentators nowadays want to see happen. Doing so unleashes an alternative law-enforcement philosophy of producer protection that has played out more or less frequently since the Sherman Act was passed in 1890. A company that convinces the FTC or the Justice Department to sue a rival for violating the antitrust laws can win competitive advantages in the courtroom that are much harder to earn in the hurly-burly of the marketplace.

In the first major antitrust lawsuit of the digital age, Microsoft was accused in the mid-1990s of monopolizing a market for Intel-chip-compatible computer operating systems, a definition that excluded all other operating systems available at the time, such as Macintosh’s OS and open-source Linux. One of the many allegations about Microsoft’s business practices was that it had limited competition in web-browsing software by bundling its own Internet Explorer product with Windows 98 and, moreover, offering it to desktop computer users at no additional charge.

The antitrust lawsuit against Microsoft was instigated, not by computer users, but by the company’s rivals and other interested parties, a coalition known as NOISE (Netscape. Oracle, Intel, Sun Microsystems, and “everyone else”). Following vigorous lobbying by NOISE, an investigation was launched by the Justice Department’s Antitrust Division after the FTC twice declined to issue a formal complaint charging Microsoft with engaging in “unfair methods of competition,” made unlawful by Section 5 of the FTC Act of 1914. A federal judge eventually declared Microsoft to be a monopolist and ordered what turned out to be some rather ineffective remedies to curb its market power.

Lina Kahn, President Biden’s appointee as Chair of the FTC, has been a relentless critic of Apple, Microsoft, Google, and today’s other large tech companies. She is unlikely to let them off as easily as Microsoft was by the Commission of a generation ago. Indeed, at the end of 2020, Ms. Khan’s FTC sued Facebook (aka Meta) to undo the company’s acquisition of WhatsApp, which her predecessors under President Barack Obama had approved in February 2014.

That action not only contributes to the uncertain business climate created by antitrust law enforcement in the past, but also continues to move the laws into regulatory territory for which they are ill-suited. Antitrust is about excessive power over prices and profits in ordinary markets, not about influence over social media or political speech.

President Biden’s endorsement of renewed antitrust activism has even raised the voices of small retailers to jumpstart enforcement of the Robinson-Patman Act, a depression-era law intended to shield Mom-and-Pop sellers from the competitive harm of low prices charged by chain stores—and today, Amazon. Few economists ever have approved of Robinson-Patman’s anti-consumer purposes and effects.

The government’s first Microsoft case is but one of many examples showing that antitrust law enforcement processes are vulnerable to special pleading by competitors of the targeted company. President Biden’s recent actions show that antitrust likewise can be exploited for political advantage, deflecting blame for imprudent monetary, fiscal, energy and anti-COVID policies.

The greatest danger of ham-handed antitrust intervention is that it can block the “creative destruction” that Austrian economist Joseph Schumpeter identified in the 1940s as a prerequisite for progress and improvement, as innovation sweeps away the old and welcomes the new.