U.N. Meeting a Farewell for Obama, and a Dress Rehearsal for Clinton

WASHINGTON — President Obama will use his final appearance at the United Nations General Assembly next week to extol the benefits of his brand of multilateral diplomacy, even as the gathering will lay bare places where that diplomacy has fallen short.

While Mr. Obama is saying his farewells, his preferred successor, Hillary Clinton, will return to the diplomatic stage, meeting with a handful of leaders, including the presidents of Egypt and Ukraine. She was a fixture at the General Assembly as secretary of state, and her presence this year will underscore the sense of political transition in the United States.

Mr. Obama, his advisers said, plans to recount the negotiations that led to the Paris climate accord and the Iran nuclear deal, and to present them as templates for dealing with future crises.

Yet the General Assembly will be shadowed by the recent nuclear test in North Korea, which demonstrated the continuing inability of the United States and other countries to force the North to abide by nonproliferation standards.

And on Tuesday, the United States will play host to a summit meeting of world leaders devoted to the mushrooming refugee crisis — a problem fueled by the five-year civil war in Syria that the Obama administration has had little success in ending.

Mr. Obama’s aides acknowledged the mixed picture. “On the one hand, there are enormous positive indicators in our world today,” Benjamin J. Rhodes, a deputy national security adviser, said Friday. “At the same time there’s a great deal of unease.”

The General Assembly is doubling as a valedictory for Mr. Obama and a dress rehearsal for Mrs. Clinton. While the president is seeking to cement his legacy and tackle unfinished business, she is using it as a way to telegraph foreign-policy priorities.

Meeting with Ukraine’s president, Petro O. Poroshenko, for example, sends a signal to President Vladimir V. Putin of Russia, who has continued to menace Ukraine along its eastern border. Her decision to meet with Egypt’s president, Abdel Fattah el-Sisi, is more complicated. She has known the former general for many years, meeting him with her husband, Bill Clinton, during previous United Nations gatherings.