WASHINGTON — With a burst of executive orders, President Joe Biden served notice on Thursday that America’s war on COVID-19 is under new command, promising an anxious nation progress to reduce infections and lift the siege it has endured for nearly a year.

At the same time, he tried to manage expectations in his second day in office, saying despite the best intentions “we’re going to face setbacks.” He brushed off a reporter’s question on whether his goal of 100 million coronavirus shots in 100 days should be more ambitious, a point pressed by some public health experts.

The 10 orders signed by Biden are aimed at jump starting his national COVID-19 strategy to increase vaccinations and testing, lay the groundwork for reopening schools and businesses, and immediately increase the use of masks — including a requirement that Americans mask up for travel. One directive calls for addressing health care inequities in minority communities hard hit by the virus.

“We didn’t get into this mess overnight, and it will take months to turn this around,” Biden said at the White House. U.S. deaths have surged past 400,000, and he noted projections that they could reach 500,000 in a month.

But then, looking directly into the TV camera, Biden declared: “To a nation waiting for action, let me be clear on this point: Help is on the way.”

House Speaker Nancy Pelosi said Friday that she will send the article of impeachment against former President Donald Trump to the Senate on Monday, triggering the start of the former president’s trial on a charge of incitement of insurrection over the deadly U.S. Capitol Jan. 6 riot.

Senate Democratic leader Chuck Schumer announced Pelosi’s intentions for a quick trial on the Senate floor Friday, rejecting Republicans’ proposal to push it to mid-February to give Trump more time to prepare his case. Schumer said there will be “a full trial, it will be a fair trial.”

Biden has also directed his intelligence community to study the threat of domestic extremism in the United States, an undertaking being launched weeks after the violent mob stormed the Capitol.

Biden took executive action Friday to speed a stopgap measure of financial relief to millions of Americans affected by the coronavirus pandemic while Congress begins to consider his much larger $1.9 trillion package.

The two executive orders that Biden signed would increase food aid, protect job seekers on unemployment and clear a path for federal workers and contractors to get a $15 hourly minimum wage.

“This can help tens of millions of families — especially those who cannot provide meals for their kids,” Biden said. “A lot of Americans are hurting. The virus is surging. ... No matter how you look at it, we need to act.”

He faces steep obstacles, with the virus actively spreading in most states, vaccine shortages, slow progress on distribution and political uncertainty over whether congressional Republicans will help him pass the $1.9 trillion economic relief and COVID response package.

Adding to the challenges are virus mutations, particularly one that has emerged in South Africa, that may make vaccines somewhat less effective. Dr. Anthony Fauci told reporters at the White House briefing that “we are paying very close attention to it.” Biden’s plan includes an expansion of research capabilities to map out the genetic structure of new variants.

On Thursday a group influential with Republican office holders lent its support to the president’s strategy. The U.S. Chamber of Commerce said, “We support the new administration’s focus on removing roadblocks to vaccinations and reopening schools, both of which are important steps to accelerating a broad-based economic recovery for all Americans.”

Biden officials have said they’ve been hampered by a lack of cooperation from the Trump administration during the transition. They say they don’t have a complete understanding of their predecessors’ actions on vaccine distribution. And they face a litany of complaints from states that say they are not getting enough vaccine even as they are being asked to vaccinate more categories of people.

Biden’s mask order for travel applies to airports and planes, ships, intercity buses, trains and public transportation. Travelers from abroad must furnish a negative COVID-19 test before departing for the U.S. and must quarantine upon arrival. Biden has already mandated masks on federal property.

Biden has directed the Federal Emergency Management Agency to begin setting up vaccination centers, aiming to have 100 up and running in a month. He’s ordering the Centers for Disease Control and Prevention to begin a program to make vaccines available through local pharmacies starting next month, building on a plan devised by the Trump administration. And he’s launching an effort to train more people to administer shots.

Biden has set a goal of having most K-8 schools reopen in his first 100 days, and he’s ordering the departments of Education and Health and Human Services to provide clear guidance for reopening them safely. States would also be able to tap FEMA’s Disaster Relief Fund to help get schools back open.

Biden is giving government agencies a green light to use the Cold War-era Defense Production Act. It allows the government to direct private industry to produce supplies needed in times of national emergency. In this case it could be anything from swabs, to masks, to certain chemicals.

Associated Press writers Collin Binkley and Josh Boak contributed to this report.