As the coronavirus upended the top echelons of the U.S. government on Tuesday — leaving President Trump convalescing in the White House, the Capitol eerily empty after lawmakers tested positive and most of the Joint Chiefs of Staff in quarantine — the president abruptly ended talks on a stimulus bill intended to shore up the nation’s pandemic-stricken economy.
Mr. Trump’s announcement Tuesday that he was ending talks with Democrats on the bill, which aimed to send more aid to Americans grappling with high unemployment and to help state and local governments stay afloat as tax collections plummet, sent the stock market sliding. It came after Jerome H. Powell, the chairman of the Federal Reserve, warned that failing to inject more federal help into the economy would risk weakening the tenuous recovery.
In multiple tweets later Tuesday, Mr. Trump appeared to backtrack on his assertion that an agreement would wait until after Election Day, at one point urging both chambers to “IMMEDIATELY Approve” a lapsed loan program for small businesses, funds to prevent airlines from furloughing or laying off workers and another round of stimulus checks. It was unclear if his tweets, which came after stocks fell, reflected a willingness to restart negotiations with House Speaker Nancy Pelosi. Both provisions have bipartisan support, but several lawmakers have pushed for them to be included in a broader package.
Taken together, the events showed the extent to which the coronavirus is continuing to dominate life in America with less than a month to go before the presidential election. The outbreak at the White House has raised concerns in the city that surrounds it. New cases are surging in the upper Midwest. The average of new reported infections across the country is creeping up again, after a late-summer decline.
In New York, which was the center of the pandemic early on but has since seen a marked decline in cases, several worrisome outbreaks led Gov. Andrew M. Cuomo to temporarily close nonessential businesses and schools in some parts of New York City and its northern suburbs.
And Mr. Trump, who left the hospital to convalesce at a White House that has become a virus hot spot, announced on Twitter that he wants to face off against his opponent, Joseph R. Biden Jr., in person next week — when he could still be contagious.
Mr. Trump said he planned to attend the debate in Miami, which is scheduled for Oct. 15. It was unclear if the debate commission would permit the debate to go ahead, given his illness, or whether Mr. Biden would agree to share the stage with him. And as both campaigns prepared for a vice-presidential debate on Wednesday, aides to Vice President Mike Pence raised objections to plans to put plexiglass dividers between him and his opponent, Senator Kamala Harris of California.
Mr. Biden, in a speech in Gettysburg, Pa., where a Civil War battlefield serves as a symbol of a country divided against itself, called for national unity and said that what “we’re experiencing today is neither good nor normal.”
Facebook removed a post from Mr. Trump on Tuesday that violated its policy against sharing misinformation about the virus, one of the few times that the social network had taken down one of his posts. In Mr. Trump’s message, he falsely suggested that the flu was deadlier than the coronavirus.
And hopes that a new vaccine could be authorized by Election Day — which Mr. Trump has relentlessly pushed for — faded after the Food and Drug Administration released updated, stricter guidelines for vaccine developers. The guidelines had been blocked by White House officials, including Mark Meadows, the chief of staff.
In pulling the plug until after the election on talks for a new bill to send aid to needy Americans, Mr. Trump accused Ms. Pelosi in a tweet of “not negotiating in good faith” and urged Senate Republicans to focus solely on confirming his nominee to the Supreme Court in the coming weeks. Mr. Trump said that he had instructed Steven Mnuchin, the Treasury secretary, to stop negotiating, sending the S&P 500 down as much as 1 percent in the immediate aftermath of his tweet. It had been up more than half a percent in the moments before. The index closed down 1.40 percent for the day.
“Our Economy is doing very well,” Mr. Trump tweeted as the market fell. “The Stock Market is at record levels, JOBS and unemployment also coming back in record numbers. We are leading the World in Economic Recovery, and THE BEST IS YET TO COME!” Mr. Biden countered on Twitter that “the President has turned his back on you.”
Mr. Trump was recovering in the White House residence, as a number of advisers and other officials stayed home, because they had either contracted the coronavirus or been near people who had.
On Tuesday night, senior administration officials confirmed that Stephen Miller, Mr. Trump’s top speechwriter and policy adviser, had tested positive for the virus.
The Capitol, normally a beehive of a workplace for 535 legislators and thousands of staff members, was eerily empty on Tuesday after Senate leaders agreed to adjourn for two weeks beginning Monday, even as Republicans were trying to fast-track Judge Amy Coney Barrett’s nomination to the Supreme Court. More than 40 senators, along with more than a dozen congressional aides and reporters, have been tested for the coronavirus since late last week, officials said on Tuesday. Three Republican senators — Mike Lee of Utah, Thom Tillis of North Carolina and Ron Johnson of Wisconsin — have tested positive in recent days.
At the highest level of the military, Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, and several of the Pentagon’s most senior uniformed leaders were quarantining after being exposed to the coronavirus, a Defense Department official said Tuesday. The official said that almost the entirety of the Joint Chiefs of Staff, including Gen. James C. McConville, the Army chief of staff, was quarantining after Adm. Charles Ray, the vice commandant of the Coast Guard, tested positive for the virus.