REUTERS - If the Russian government is behind the theft and release of embarrassing emails from the Democratic Party, as U.S. officials have suggested, it may reflect less a love of Donald Trump or enmity for Hillary Clinton than a desire to discredit the U.S. political system.

A U.S. official who is taking part in the investigation said that intelligence collected on the hacking of Democratic National Committee emails released by Wikileaks on Friday "indicates beyond a reasonable doubt that it originated in Russia."

The timing on the eve of Clinton's formal nomination this week for the Nov. 8 presidential election has raised questions about whether Russia may have been trying to hurt her, to help Trump, her Republican rival, or to fan populist sentiment against establishment politicians as it has sought to do across Europe in recent years.

"Certainly Russia has become a master at manipulating information for their strategic goals: Witness the information bubble they have created for their threatening behavior in the Crimea, the Ukraine and elsewhere," said former CIA and National Security Agency director Michael Hayden. "A step like this, however, would be really upping their game."

The emails showed that DNC officials explored ways to undermine U.S. Senator Bernie Sanders' presidential campaign against Clinton and raised questions about whether Sanders, who is Jewish, was really an atheist.

The disclosures confirmed Sanders' frequent charge that the party played favorites against him and clouded a party convention Clinton hoped would signal unity, not division.

PUTIN'S COUNTERPUNCH?

Two U.S. intelligence officials, speaking on condition of anonymity, said the hack could be part of a broader campaign by Russian President Vladimir Putin to push back against what he thinks is an effort by the European Union and NATO, a military alliance of European and North American democracies, to encircle and weaken Russia.

One of the officials called the fear "a hangover" from Putin's service in the KGB, the Soviet intelligence agency.

"Time and again, we're seeing Russia push back at what Putin considers Russia's mortal enemies," said the other official. "He's been actively attacking the U.S.-backed rebels in Syria, buzzing ships and planes in the Black Sea and the Baltic, not to mention invading Ukraine and seizing Crimea. This fits the pattern."

Despite Clinton's short-lived attempt as secretary of state to "reset" U.S.-Russian relations after U.S. President Barack Obama took office in 2009, the leaked emails could damage a candidate the Kremlin may consider hostile and benefit her opponent, who has been friendlier.

Putin accused Clinton of stirring up protests against his rule after a December 2011 Russian parliamentary election that was marred by allegations of fraud, saying she had encouraged "mercenary" Kremlin foes by criticizing the vote.

"She set the tone for some opposition activists, gave them a signal, they heard this signal and started active work," Putin told supporters.

Asked about claims that Russian intelligence had hacked the DNC to obtain the emails, Wikileaks founder Julian Assange told NBC News' Richard Engel "there is no proof of that whatsoever" and said "this is a diversion" pushed by the Clinton campaign.