Will be a test for everyone……

Pope Francis’s visit to the United States will ensnarl traffic in three different cities, clog the streets with tens of thousands of tourists and strain the government’s security capacity like perhaps never before.

Officials have been planning for the pontiff’s landmark visit to Washington, Philadelphia and New York for months, with the Secret Service, the FBI and a handful of other federal, state and local agencies all involved in keeping him safe.

But Francis’s stay in Washington, beginning Tuesday, isn’t the only security challenge facing law enforcement agencies.

The pope’s visit also bumps up against the state visit of Chinese President Xi Jinping, as well as the United Nations General Assembly, which begins early next week.

All together, it could represent the largest domestic security deployment the country has ever seen, stretching the government’s limits months after slip-ups at the Secret Service forced its director to step down.

“If the Secret Service were the Avengers I’d be worried about this — I’m only half kidding,” said Dan Bongino, a former Secret Service agent who served while Pope Benedict XVI visited the U.S. in 2008. Bongino unsuccessfully ran for the House in 2014 and the Senate in 2012 as a Republican from Maryland.

“It’s the equivalent of multiple presidential inaugurations occurring in multiple cities all at the same time.”

Francis arrives in Washington for a three-day stay on Tuesday, fresh off the heels of a trip to Cuba.

On Thursday, he heads to New York, where he will celebrate Mass in Madison Square Garden and meet with U.N. officials. On Saturday morning, he’ll go to Philadelphia and hold a prayer vigil with the World Meeting of Families — a global meeting of Catholic families — before heading back to Rome on Sunday.

More than 1 million people are expected to attend Francis’s outdoor Mass in Philadelphia alone.

The Department of Homeland Security (DHS) has labeled Francis’s visit a “national special security event,” putting it with the rare company of global summits, state funerals and the Olympics.

The White House insists the Secret Service is well prepared for the whirlwind week, which will culminate in Obama’s trip to New York for the U.N. General Assembly on Sunday.

“It’s not an exaggeration to say that the United States Secret Service has been planning for these activities for months and if not years,” press secretary Josh Earnest told reporters on Monday. “They are well aware of the significant challenges.”