WASHINGTON — President Trump’s national security adviser, John R. Bolton, fleshed out his boss’s “America First” foreign policy on Monday, disparaging an international organization vilified by conservatives and reaffirming a pro-Israel tilt by announcing the closing of the Palestine Liberation Organization’s office in Washington. But on one of Mr. Trump’s signature projects, nuclear diplomacy with North Korea, he parted company.
On the same day that the White House welcomed a letter to Mr. Trump from Kim Jong-un, proposing another meeting of the two leaders, Mr. Bolton struck a markedly less optimistic tone, expressing frustration that Mr. Kim had not yet begun to fulfill his promise to rid North Korea of its nuclear weapons.
“The possibility of another meeting between the two presidents obviously exists,” Mr. Bolton said, “but President Trump can’t make the North Koreans walk through the door he’s holding open. They’re the ones that have to take the steps to denuclearize, and that’s what we’re waiting for.”
Mr. Bolton’s remarks came after a speech to the Federalist Society — his first major public appearance since taking his job in April — in which he threatened the International Criminal Court with sanctions if it investigated American troops in Afghanistan. His announcement of the closing of the P.L.O. office reinforces how far the White House has moved from the role of a broker in the region.
Taken together, Mr. Bolton’s unyielding remarks and the White House’s upbeat analysis revealed the crosscurrents in this White House: The president’s aides have translated his instincts into a range of conservative policies, but they remain skeptical of — and sometimes seek to curb — his unswerving belief that personal relationships can triumph over geopolitical realities.
Days after Mr. Trump expressed high hopes for the letter from Mr. Kim, the White House press secretary, Sarah Huckabee Sanders, described it as “very warm, very positive.” She said Mr. Kim wanted to schedule a follow-up to the Singapore summit meeting in June, and that the White House was open to it.
“The president has achieved tremendous success with his policies so far,” Ms. Sanders said. “And this letter was further evidence of progress in that relationship.”
The military parade held in North Korea last weekend was another encouraging sign, she said, because it did not feature the usual display of intercontinental ballistic missiles that could threaten the American homeland. Mr. Bolton was asked about the same parade but did not credit the North Koreans with any symbolic show of good will. He instead emphasized that Mr. Kim had agreed to give up his nuclear arsenal in a year.
A longtime fixture in conservative foreign policy circles, who worked in the George W. Bush administration, Mr. Bolton has kept a lower profile since he replaced Lt. Gen. H. R. McMaster than some of Mr. Trump’s other foreign policy advisers.
He has been especially circumspect on North Korea since he argued, early in his tenure, that Libya could serve as a model for North Korea’s disarmament. The comparison drew a furious response from North Korean officials and nearly derailed Mr. Trump’s meeting with Mr. Kim.
Yet officials said Mr. Bolton has moved swiftly to assert control over other issues he cares about: Iran, the Middle East and America’s role in international organizations (he had a famously rancorous stint as ambassador to the United Nations under Mr. Bush).
That was clear on Monday in his virulent condemnation of the International Criminal Court. As an under secretary of state and later ambassador, he championed Mr. Bush’s decision not to join the court and led a public campaign to discredit it.
“Today, on the eve of Sept. 11, I want to deliver a clear and unambiguous message on behalf of the president,” Mr. Bolton declared. “The United States will use any means necessary to protect our citizens and those of our allies from unjust prosecution by this illegitimate court.”
“We will ban its judges and prosecutors from entering the United States,” he added. “We will sanction their funds in the U.S. financial system, and we will prosecute them in the U.S. criminal system. We will do the same for any company or state that assists in an I.C.C. investigation of Americans.”
Mr. Bolton said his remarks were prompted by indications that the court wants to investigate the conduct of American troops in Afghanistan. He said the goal was to stop the investigation in its tracks, and offered a litany of familiar arguments against the court: It infringed on American sovereignty, had unchecked power and was “ineffective, unaccountable, and indeed, outright dangerous.”
Mr. Bolton said his campaign against the court was one of his proudest moments. After he left the Bush administration in 2006, the White House showed a little less resistance to the court’s work, even expressing support for its investigation of atrocities in Darfur.
Under President Barack Obama, the United States began helping the court in investigations and shifted to what Harold Koh, then the State Department’s legal adviser, called “positive engagement.”
Still, the United States never joined the court. And with Mr. Bolton back in power, the White House has swung back to the language of 2002 and 2003.
“The largely unspoken, but always central, aim of its most vigorous supporters was to constrain the United States,” Mr. Bolton said.
Given Mr. Bolton’s history, lawyers and human rights activists said they were not surprised that the Trump administration would revert to a hostile stance. But some said they were troubled by his threats against the judges on the court.
“You don’t win cases by threatening judges,” said Stephen J. Rapp, former ambassador at large for war crimes issues under Mr. Obama. “We can prevent the prosecution of Americans, not by threatening judges, but by showing that we thoroughly investigated and found no cases where the evidence met the burden of proof.”
Mr. Bolton said he did not oppose all international organizations — NATO, he said, advanced American interests. But he said the Trump administration had moved systematically to withdraw from, or deny funding to, organizations like the United Nations Human Rights Council, which he said infringed on American sovereignty.
His announcement that the United States would close the P.L.O.’s office in Washington deepens the rift between the Trump administration and the Palestinians, which opened up after Mr. Trump announced he would recognize Jerusalem as the capital of Israel.
“This dangerous escalation shows that the U.S. is willing to disband the international system in order to protect Israeli crimes,” said Dr. Saeb Erekat, the Palestinians’ chief negotiator.
Mr. Bolton said the administration had acted in part because the Palestinians had not shown good faith in trying to negotiate a peace agreement with Israel. The White House has yet to present its peace proposal, which Mr. Bolton said on Monday was still being refined.
In the meantime, Mr. Trump has eliminated hundreds of millions of dollars of aid to Palestinian refugees and economic development in the West Bank and Gaza. He recently cut $25 million in funding for hospitals used by Palestinians in East Jerusalem.
Former diplomats said the decision to close the P.L.O.’s office would have little practical effect on the administration’s dealings with the Palestinians. Since the 1990s, American administrations have dealt directly with the Palestinian Authority in the West Bank city of Ramallah.
But Aaron David Miller, a senior fellow at the Woodrow Wilson International Center for Scholars, said the office symbolized American recognition of Palestinian nationalism and gave the Palestinians “an important P.R. hook on which Palestinians could hang their hat.”
Shutting it down, he said, was another attempt by the White House to pressure the Palestinians in the international arena.
“In decades of working on this issue,” Mr. Miller said, “I’ve never seen an administration so committed to Israel and at the same time so hostile to Palestinians without a coherent policy objective on both ends.”
Marlise Simons contributed reporting from Paris.