In a campaign ad in 2018 boasting that he was “so conservative,” Brian Kemp brandished a chain saw and declared his tool “ready to rip up some regulation.”

Two years later, the regulation to which Georgia’s Republican governor is turning his attention is a municipal order requiring people to wear masks in Atlanta, among other precautions designed to arrest transmission of the novel coronavirus, which has sickened nearly 150,000 Georgians.

Now, Kemp’s instrument is not a chain saw. Instead, he is wielding a lawsuit and request for an injunction barring the city’s Democratic mayor and contender for the vice presidential nomination, Keisha Lance Bottoms, from enforcing her ordinance or speaking to the media about her authority to do so.

The complaint was filed in Fulton County Superior Court, where a hearing scheduled for Tuesday morning was delayed after the judge assigned to the case was recused. The case marks the latest flash point over face coverings, which help block the airborne particles and tiny droplets that spread the deadly virus but are seen by some conservatives and anti-government activists as “medical tyranny.”

The legal contest also exposes in newly stark terms the standoff between Republican governors and the Democratic mayors of the biggest cities in their states, which could be some of the hardest-fought battlegrounds in the November election.

Kemp, dogged by claims of voter suppression in the 2018 election that he refereed as Georgia’s secretary of state, has embraced his role as an avatar for these conflicts, which are flaring during the health emergency. He has eschewed expert consensus, frequently casting his response to the pandemic in ideological terms reminiscent of his incendiary campaign ads.

“He is of the mind-set that people don’t require government to tell them what to do,” said Doc Eldridge, who developed a rapport with Kemp in the 1990s when Eldridge was a district commissioner and then mayor of Athens-Clarke County and Kemp was working as a local developer, before he ran for a state Senate seat in 2002.

When states first began lifting coronavirus lockdown measures in the summer, tensions around face masks had been mounting since the CDC first recommended them. (The Washington Post)

Kemp, who reported a net worth of $5.2 million in 2018, does not believe, Eldridge said, “that government is the answer to all of our problems.”

He does, however, believe in President Trump, whom he welcomed, unmasked, to Georgia last week. With his move to void Atlanta’s July 10 ordinance, which also returns the city to Phase 1 of its reopening, Kemp has turned his state into ground zero for a hasty return to normal hewing to Trump’s vision for an abrupt economic restart.

The governor’s litigious response to Bottoms has baffled public health experts and even some business leaders in the state. They say his heavy-handed approach with local leaders — even as he encourages Georgians to wear masks — limits the effectiveness of one of the best tools for keeping the virus at bay, which is necessary for consumer confidence. Major retailers, such as Walmart, have acknowledged as much in requiring customers to wear face coverings.

“Every relevant scientific body is saying that masks are essential,” said K.M. Monirul Islam, an epidemiologist who runs the public health program at Augusta University.

Kemp has set himself apart even from fellow Republicans. More than half of all states have statewide mask mandates, after Alabama and Arkansas — both conservative states led by conservative Republican governors — adopted them last week. Republican governors and Trump acolytes in Arizona and Florida have authorized county and municipal leaders to make their own rules about face coverings.

Kemp, meanwhile, is unmoved, vowing to stand in the way of “disastrous policies” — as he labeled the orders in Atlanta — that “threaten the lives and livelihood of our citizens.”

That position upends local control, long a principle claimed by conservatives. And the target placed on Atlanta intensifies the political overtones of the litigation, say mayors of other Georgia cities, from Augusta to Athens to Savannah, whose mask ordinances remain in effect.

“It’s hard to fully figure out what is in somebody else’s mind, but it’s no secret that the governor is a strong ally of the president, and it’s also no secret that Mayor Bottoms is a strong ally of Vice President Biden,” said Kelly Girtz, the mayor of Athens, Kemp’s hometown. “That suggests there may be some political intent.”

Atlanta is in the governor’s crosshairs because the mayor’s actions extend beyond requiring masks and include a reversion to a previous phase of reopening, said Candice Broce, a spokeswoman for the governor. But the complaint, which also names members of the city council as defendants, lists as the mayor’s first offense making masks mandatory.

Kemp’s allies maintain he favors masks — even completing a “wear a mask” tour of the state — while seeking to strike a balance with economic interests that depend on uniform rules across the state. The lawsuit aims to prevent “mixed messages that are being sent out to businesses and restaurants,” said state Rep. Terry Rogers, among the governor’s legislative floor leaders.

The Georgia Chamber of Commerce echoed that concern, backing the governor’s move and, in a statement, saying businesses “should not be forced to enact an ever-changing patchwork of regulations.” Municipal chambers have taken different views. David Bradley, who heads the local business association in Athens, said he supports the city’s mask mandate.

“It would seem that science is on the side of wearing masks, and that long-term economic sustainability is on the side of wearing masks,” he said. The Metro Atlanta Chamber of Commerce did not respond to a request for comment.

The governor’s office has evolved in its position on face coverings — growing less stringent as the pandemic has worsened. An executive order in April beginning the state’s reopening required all restaurant employees to wear face coverings “at all times.” Kemp’s executive counsel, David Dove, stressed that point in an email to the state’s restaurant association, part of correspondence released through a public records request.

“Face covering is a requirement for all restaurants,” he wrote on April 27, as daily new cases hovered around 500. “Does not have to be a specific type of mask but has to be a face covering.”

A new executive order on June 11, as daily new cases neared 1,000, eased that restriction, specifying that restaurant employees “are only required to wear face coverings when they are interacting with patrons.”

The governor’s latest move to ease up on mask requirements, in this case seeking to invalidate the Atlanta ordinance, came as average daily cases soared above 3,000.

The rapidly increasing ­caseload, however, is not reflected in some of the health department’s data visualizations, which display cases per 100,000 residents across different regions of the state. The color scheme has not shifted even as the total number of cases has increased nearly 50 percent in the past two weeks. A spokeswoman for the health department, Nancy Nydam, said the maps are “not designed to show increases over time, but rather to show density by location and differences between counties.”

Concern about how the state is presenting data to the public is long-standing. In May, the governor’s office apologized after a graph was posted showing a downward trajectory of cases — but only because the x-axis was not in chronological order.

Case counts and the health precautions they recommend are particularly vexed in Georgia because of Kemp’s unorthodox approach to managing the outbreak. He was one of the last governors to shut down his economy, explaining when he did act, in early April, that he had only recently learned that asymptomatic carriers can spread the virus — a warning long articulated by scientists and broadly shared with the public.

Three weeks later, Kemp declared he was reopening Georgia’s economy, making him among the first governors to do so. The decision came after Trump had urged governors to roll back restrictions, also calling on protesters to “liberate” their states. But the speed with which Kemp acted to reignite commercial activity drew rebuke even from the president.

“I told him, ‘I totally disagree,’ ” Trump said.

Kemp, said University of Georgia political scientist Trey Hood, “was thrown under the bus.”

Whatever ill will may have resulted, however, has not lasted. When Trump — with no mask, in violation of the city’s rules — visited Atlanta last week, a masked Kemp was at the airport to welcome him.

His relationship with Bottoms, by contrast, has been badly strained. In addition to the mask issue, the governor and the mayor of the state’s largest city have tangled over whether the National Guard was needed to quell unrest following the fatal shooting of a black man, Rayshard Brooks, by a white police officer.

The lawsuit caused tensions to boil over.

“The governor has done many things as of late and said many things as of late that, quite frankly, are simply bizarre,” Bottoms said Sunday on CBS’s “Face the Nation.” “He filed a 124-plus-page lawsuit against me this week calling for an emergency injunction to stop me from speaking about his orders. If the governor of this state had his way, I would not be allowed to speak with you today.”

Bottoms — who has tested positive for the coronavirus, along with her husband and one of their sons — has said that the mask ordinance could bring down infection rates and save lives.

“Atlanta sits in two counties in this state, two of the highest counties for infection rates from covid-19. So this is not about politics. This is about people,” she said.

Her argument has been bolstered by the Trump administration’s scientific advisers, who have been calling on the public to wear masks since early April, and health experts at the Atlanta-based Centers for Disease Control and Prevention. Last week, CDC Director Robert Redfield cited studies showing the beneficial impact of masks in saying that widespread use could “bring this epidemic under control” within one or two months.

Georgia’s experience with the virus has not been as bad as in states such as Florida, Texas and Arizona. But cases are rising fast.

In the past week, the state has averaged more than 3,000 new infections a day. A little over a month ago, the average was fewer than 1,000. More than 3,100 people in Georgia have died of the coronavirus.

The Harvard Global Health Institute rates Georgia as among the 11 states where the coronavirus is spreading so rapidly that governors should institute stay-at-home orders.

Kemp, however, has shown no interest in considering the idea. His hard line could help solidify his standing among Republicans, observers said.

“It probably helps him with his base. Atlanta is not a place where Georgia Republicans are going to get a lot of votes,” Hood said.

The effect on the state’s broader political proclivities is less clear, especially with Bottoms a possible running mate for Joe Biden and Kemp’s own by-a-whisker victory serving as a reminder of just how divided modern Georgia has become.