What Happens Now That Julian Assange is Implicated in Russian Espionage?

WASHINGTON — The Obama administration on Friday formally accused the Russian government of stealing and disclosing emails from theDemocratic National Committee and from a range of prominent individuals and institutions, immediately raising the issue of whether President Obama would seek sanctions or other retaliation for the cyberattacks.

In a joint statement from the director of national intelligence, James Clapper Jr., and the Department of Homeland Security, the government said the leaked emails that have appeared on a variety of websites were “intended to interfere with the U.S. election process.” The emails were posted on the WikiLeaks site and newer ones under the namesDCLeaks.com and Guccifer 2.0.

“We believe, based on the scope and sensitivity of these efforts, that only Russia’s senior-most officials could have authorized these activities,” the statement said. It did not name President Vladimir V. Putin, but that appeared to be the intention.

For weeks, aides to Mr. Obama have been debating a variety of possible responses to the Russia action, including targeted economic sanctions and authorizing covert action against the computer servers in Russia and elsewhere that have been traced as the origin of the attacks.

The statement said that the recent “scanning and probing” of election systems “in most cases originated from servers operated by a Russian company,” but did not say the Russian government was responsible for those probes.

The president’s aides have also been debating whether to publicly attribute the attacks to Russia. Mr. Obama had decided against taking that stance in other cases where cyber techniques were used to steal tens of thousands of emails from the unclassified system of the State Department, the White House and the Joint Chiefs of Staff.

As recently as Wednesday, the director of the National Security Agency, Adm. Michael S. Rogers, refused to accuse the Russians of the cyberattack, even while talking at length about how to secure the American election system from foreign data manipulation and information warfare.

The administration’s announcement came only hours after Secretary of State John Kerry called for the Russian and Syrian governments to face a formal war-crimes investigation for attacking civilians in Aleppo and other parts of Syria. Taken together, the two moves mark a sharp escalation in Washington’s many confrontations with Moscow this year.

With little more than a month to go before the presidential election, Mr. Obama was under pressure to act now on the hacking, according to a senior administration official, who spoke on the condition of anonymity to discuss internal White House deliberations. The timing of Friday’s announcement was decided in part because a declaration closer to Election Day would appear to be political in nature, the official said.

The subject came up in the first presidential debate, with Hillary Clinton, the Democratic nominee and a former Secretary of State, blaming Russia for the attacks. Her Republican rival, Donald J. Trump, said there was no evidence that Russia was responsible, suggesting that the Chinese could be behind it, or it “could be somebody sitting on their bed that weighs 400 pounds.”

The question now is how Mr. Obama might respond without setting off an escalating cyberconflict. One possibility is that the announcement itself — an effort to “name and shame” — will deter further action.

The identification of Russia was hardly a surprise: In late July, American intelligence officials told The New York Times that they had “high confidence” that the Russian government was behind the hack of the Democratic National Committee.

The hack led to the resignation of Representative Debbie Wasserman Schultz, Democrat of Florida, as chairwoman of the committee, after the leaks suggested the committee had favored Mrs. Clinton in the nominating fight over Senator Bernie Sanders of Vermont.