(CNN)Democratic presidential nominee Joe Biden accused President Donald Trump of "a life-and-death betrayal of the American people" hours after journalist Bob Woodward revealed ahead of the publication of his new book, "Rage," that Trump had concealed the true threat posed by coronavirus.
While campaigning in Michigan on Wednesday, Biden pointed to Trump telling Woodward in a recorded February interview that the virus was more deadly than the flu, airborne and highly contagious.
"He knew it and purposely played it down. Worse, he lied to the American people. He knowingly and willingly lied," Biden said about the threat posed by the virus, which has now left more than 185,000 Americans dead.
"It's beyond despicable. It's a dereliction of duty. It's a disgrace," Biden said. "He failed to do his job on purpose. It was a life-and-death betrayal of the American people."
Trump's comments downplaying the virus come as he is trailing Biden in national polls just three weeks from the first debate. They follow last week's report in The Atlantic -- confirmed in part by other news outlets but vehemently denied by Trump -- that the President had called those wounded and killed at war "losers" and "suckers."
Biden told autoworkers Wednesday that Trump "has broken just about every promise he's ever made to the American worker."
Seizing on Trump's comments about war dead, he added: "Did you really expect anything different from this guy? From someone who called those of you and those who are serving in uniform, who have given their lives for this country, losers and suckers?"
The former vice president was in Michigan to make an economic case against Trump in Macomb County, rolling out a plan to stop businesses from moving jobs overseas in one of the nation's most important battlegrounds in November's election.
Macomb County is a swing region that Trump won by 12 percentage points in 2016 -- making him the first Republican to win the county since 1988.
Biden's speech is part of his campaign's efforts to counter Trump's rosy predictions of a rapid economic recovery once the coronavirus pandemic recedes and a vaccine becomes available.
Biden's trip comes the day before Trump will visit Michigan for a rally in Freeland, just northwest of Saginaw. Wednesday marks Biden's first visit to the state -- part of the "blue wall" that also includes Pennsylvania and Wisconsin that Trump toppled against Hillary Clinton in 2016 -- since March 9, where he held a rally in a Detroit high school gym on the eve of the state's Democratic presidential primary. The next day, Biden halted in-person campaign events because of the pandemic.
"I believe this race is tightening up. We've seen polling to that effect, and I'm not surprised by it," Michigan Gov. Gretchen Whitmer, a Democrat and co-chair of Biden's campaign who won Macomb County by four points in 2018 on the way to a 10-point win statewide, said in an interview with CNN on Tuesday.
Biden's campaign on Wednesday unveiled a new proposed tax policy and package of executive actions that would be aimed at preventing companies from moving jobs overseas.
He is proposing adding a 2.8 percentage point surtax on top of a 28% tax rate, for a total rate of 30.8%, on profits from American companies that produce goods overseas and then sell those goods back into the US market.
Meanwhile, he is proposing an advanceable 10% tax credit for "companies making investments that will create jobs for American workers," a campaign document said.
Biden would also close corporate loopholes in the 2017 tax law Trump signed, and would create a "Made in America" office within the Office of Management and Budget to enforce "Buy American" policies, the campaign document detailing his plan said.
In Warren on Wednesday, Biden said he would be the most pro-labor union president in history.
"Donald Trump and I have a pretty different philosophy when it comes to giving our word," Biden said. "Mine means something."
Biden's visit to Michigan comes as he begins traveling to swing states ahead of the general election, even as the pandemic limits his events to small, invitation-only crowds. Biden has also traveled recently to Pennsylvania and Wisconsin, and his campaign said Wednesday he will travel to Florida next week.
Biden closed his event Wednesday in Michigan by holding up a note card he carries with him daily. The card includes the number of US troops killed and wounded in Iraq and Afghanistan, as well as the number of coronavirus cases and fatalities both in the United States and among the US military.
"Folks, every one of these lives matter," Biden said. "Every one of these lives left somebody behind grieving. We can't ever forget them -- ever, ever forget them."
This story has been updated with comments from Biden on Wednesday.