The U.S. Secret Service is once again embroiled in controversy following a second apparent attempt on the life of former President Donald Trump.

The agency came under criticism in July when a gunman at a Trump rally in Butler, Pa., was able to fire multiple shots at the Republican presidential nominee, killing one rally attendee, striking Trump's ear and wounding two others.

The Secret Service had been made aware of a "suspicious male" loitering near the rally, but officials lost track of him.

Now, just over two months later, a second alleged gunman was able to make it within several hundred yards of Trump in West Palm Beach, Florida.

This time, the man, armed with a semiautomatic rifle, was thwarted when an agent saw the barrel of the man's gun sticking out through the bushes as the former president played golf. The agent began shooting at the armed man, and the gunman did not return fire, according to authorities.

Trump was uninjured in that event, and in a Monday interview on the social media platform X, he praised Secret Service agents for having done a "great job" in protecting him.

But both incidents added to criticism of the agency for letting danger get so close to a person under its protection.

What is the Secret Service?

The Secret Service is the official protection system for sitting and former presidents and vice presidents; their families; major party nominees to those offices; visiting foreign heads of state; and others. As of now, the agency has 36 people under routine protection, including President Biden and his family, as well as former President Barack Obama and former first lady Michelle Obama.

The agency was founded in 1865 under the Department of the Treasury to help combat counterfeiting of U.S. currency following the Civil War. Ironically, President Abraham Lincoln signed approval to start the agency on the same day he was shot.

It wasn't until the 1901 assassination of President William McKinley that the Secret Service would be tasked with protecting the president.

In the years since, the agency has been at the forefront of a number of history-altering events in U.S. politics, including the assassination of President John F. Kennedy and serious attempts on the lives of Presidents Gerald Ford and Ronald Reagan.

Following the Sept. 11, 2001, attacks on the U.S., the agency shifted from the Treasury Department to the Department of Homeland Security, which was created in response to the attacks.

The Secret Service's reach as a law enforcement agency has expanded broadly since then.

What are the problems with the agency?

The agency aims for a "zero-fail" mission. But the recent attempts against Trump have called into question the agency's leadership and its operatives' ability to do their jobs.

The Secret Service is currently helmed by acting Director Ronald Rowe, who stepped into the role after Kimberly Cheatle's resignation in the wake of the attempt on Trump's life in July.

Lawmakers slammed Cheatle for the Secret Service's response to that shooting, including failures to communicate with local law enforcement officials before and during Trump's rally in Butler and its lack of a good plan to secure the roof that ultimately gave the gunman a clear line of sight to shoot at Trump.

The Department of Homeland Security's Office of Inspector General in July launched its own review into the Secret Service's process for securing the Trump rally.

At a news conference on Monday, Rowe defended his agency and said that following the Pennsylvania shooting, he ordered a paradigm shift of being more proactive instead of reactive. But, he said, the organization needs help.

"We have done more with less for decades," Rowe said. "We have immediate needs right now."

The Secret Service operates on a budget of just over $3 billion. It employs some 3,600 special agents, 1,600 Uniformed Division officers and more than 2,000 additional personnel.

In a meeting last week with members of Congress, Rowe asked lawmakers for better training for countersnipers and the ability to hire more staff, he said. It wasn't immediately clear how much extra money or personnel the agency is asking for.

Biden similarly noted the agency's issues on Monday, telling reporters: "The service needs more help."

What is Congress' role?

Various committees in Congress have launched their own probes into the incidents around Trump.

Following the July assassination attempt, the U.S. House established a task force to investigate the shooting, while the Senate Homeland Security and Governmental Affairs Committee launched an investigation.

Speaking on Tuesday in a fireside chat with the right-wing America First Policy Institute think tank, House Speaker Mike Johnson, R-La., said the House task force would expand to include an investigation into the Sunday incident as well.

But lawmakers are divided on whether the Secret Service's problems could be fixed by more money.

Johnson acknowledged that the agency faces problems but questioned whether those issues needed to be solved with additional funding.

"The Secret Service, as you've seen reported, suggests that they have a manpower shortage. And look, it's about allocation of resources," he said. "I'm not so sure it's a funding issue, but Congress will be willing to do what's necessary."