WATCH: Vance addresses Paxton endorsement, DOJ fund in White House briefing

With his press briefing coming shortly after President Donald Trump's endorsement in the Texas Senate primary, Vice President JD Vance stressed that state Attorney General Ken Paxton will be a "great senator for the people of Texas."

Watch in our video player above.

Echoing Trump's endorsement statement, Vance noted that he has known U.S. Sen. John Cornyn for a long time, but that ultimately, Paxton was the one who was there for the president.

"I think the message that people should take from this is fundamentally, you have got to serve the people who sent you," Vance said. "And if you don't do that, you're going to find yourself out of step with voters or out of step with the president of the United States. And that's not a good place to be politically."

Vance briefing underway

The vice president began his turn in the White House press briefing room on Tuesday by making a joke about what reporters to avoid.

"I've got my cheat sheet here, so I know who to call on, most importantly, who not to call on," Vance quipped. (U.S. Secretary of State Marco Rubio, during his stint at the lectern, made a similar joke.)

In his opening remarks, Vance announced that he would deliver the commencement address at the U.S. Air Force Academy next week and touted the work of his anti-fraud task force.

Vance says Iran would be 'first domino' in race by countries to get nuclear weapons

Vance resurrected the Cold War-era "domino theory" to justify the Iran war, saying that a failure to stop that country's nuclear ambitions would lead to other countries pursuing atomic weapons.

"If you have every country in the world scrambling to try to get a nuclear weapon, it would make us all much less safe," Vance told reporters at the White House briefing. "And Iran would really be the first domino."

During the Cold War with the Soviet Union, U.S. policymakers argued that if a country went communist, it could cause neighboring nations to fall like dominoes into communism as well.

This led to efforts to contain the spread of communism and resulted in American interventions in Vietnam and other nations.

The Vietnam War lasted nearly 20 years.

Vance says no part of DOJ fund will go to Trump, his family

As he defended the new Justice Department weaponization fund, Vance said unequivocally that neither the president, his administration, nor his family will benefit from the new $1.8 billion pot of money.

"Is a dollar of this money going to the Trump administration? No," Vance said. "Is a dollar of this money going to Donald Trump personally? No. Is a dollar of this money going to Donald Trump's family? No."

Vance said that anyone can apply to be compensated from the fund and defended using taxpayer money for it.

"Whenever the United States government incurs legal expenses, it pays out those legal expenses," Vance said.

Vance says Pope Leo XIV's AI views will 'have some influence,' but doesn't necessarily agree

Vance said that the expected encyclical from Pope Leo XIV on artificial intelligence will be "very important" and "have some influence," but he said he may or may not agree with its findings.

Vance noted that the previous Pope Leo led the Roman Catholic church during the industrial revolution and a transformation that, "according to a lot of people, led to the rise of fascism and communism in Europe."

Vance said the Trump administration wants to take a "pro-innovation" approach to AI and outpace other countries in developing the technology.

But the vice president said the administration wants to protect people's data and privacy as AI is developed for both the economy and national security.

"I'm not going to get ahead of the executive order or any other actions that are going to come out, but we're trying to balance those two things" regarding innovation and protecting people's privacy, Vance said.

Vance seizes opportunity to say he's focused on his current job, not a presidential campaign

The vice president remarked on a reporter referring to him as a "potential future candidate" to say: "I'm not a potential future candidate. I'm a vice president."

"I really like my job, and I'm going to try to do as good of a job as I can," Vance said.

The vice president has said similar when brushing aside questions about whether he will run for the White House in 2028.

Vance says Europe needs to 'take more ownership' on defense

Asked about President Trump's plans regarding troop levels in Poland, Vance said the administration's focus is to promote "European independence and sovereignty."

"Poland is capable of defending itself with a lot of support from the United States," Vance said.

The vice president also disputed that the administration was reducing troop levels in Poland.

"What we did is that we delayed a troop deployment that was going to go to Poland," Vance said. "That's not a reduction. That's just a standard delay in rotation that sometimes happens in these situations."

Vance said that shooting at San Diego mosque was personal for his family

Vance said his wife, Usha, would likely have known families affected by the deadly shooting on Monday at the Islamic Center of San Diego.

The vice president noted that his wife's family lives in San Diego and that he texted her after the shooting to see if she knew anyone at the center.

"And she said, 'Absolutely. I would have known some people, or at least their parents, who might have actually used the services at this community center,'" Vance said at the White House briefing.

He said the center was near a restaurant where his family eats during visits to San Diego.

Vance added "that type of violence in the United States of America is reprehensible."

Two teenage suspects killed three men in the shooting.

Vance says Iran is 'not a forever war'

The vice president continued to defend the administration's strategy in Iran, saying that active conflict lasted about as long as President Trump's initial four- to six-week prediction and that the two countries were currently in a ceasefire.

"We're going to get a good settlement that actually gets the American people what they need, or we're going to go back to a kinetic operation."

Vance, a skeptic of military intervention abroad, said, "This is not a forever war."

"We're going to take care of business and come home," he said.