Before you press the "close" button, hear me out. My question is: was there a non-partisan assessment as to whether Russia's influence campaign not just helped Trump get elected but made his presidency possible? In some swing states, there were pretty narrow leads. Was there a scientific assessment to determine whether the influence was significant enough to actually change the outcome? If so, what were the conclusions of such an assessment? By "influence campaign", I mean both the campaign in the social media and hacks.
It's difficult to measure the impact Russia's disinformation had on the election because there was no control group. Essentially every American was exposed to Russian disinformation, which means we can't compare the responses of different groups to assess the amount of influence Russia directly had on American citizens.
Wikipedia has the following to say on Impact on election result, minus the claims made by partisan politicians which I cut out.
As of October 2018, the question of whether Donald Trump won the 2016 election because of the Russian interference had not been given much focus—being declared impossible to determine, or ignored in favor of other factors that led to Trump's victory. Joel Benenson, the Clinton campaign's pollster, said we probably will never know, while Richard Burr, the Republican chairman of the Senate Intelligence Committee, said "we cannot calculate the impact that foreign meddling and social media had on this election". Michael V. Hayden, a former director of the CIA and the NSA, believes that although the Russian attacks were "the most successful covert influence operation in history," what impact they had is "not just unknown, it's unknowable." Statistician Nate Silver, writing in February 2018, described himself as "fairly agnostic" on the question, but notes "thematically, the Russian interference tactics were consistent with the reasons Clinton lost."
Clinton supporters have been more likely to blame her defeat on campaign mistakes, Comey's reopening of the criminal investigation into her emails, or to direct attention to whether Trump colluded with Russia.
On the other hand, a number of former intelligence and law enforcement officials, at least one political scientist and one former U.S. president argue that Russian interference was decisive because of the sophistication of the Russian propaganda on social media, the hacking of Democratic Party emails and the timing of their public release, the small shift in voter support needed to achieve victory in the electoral college, and the relatively high number of undecided voters (who may be more readily influenced). James Clapper, the former director of National Intelligence, told Jane Mayer, "it stretches credulity to think the Russians didn't turn the election ... I think the Russians had more to do with making Clinton lose than Trump did." Ex-FBI agent, Clint Watts, writes that "without the Russian influence ... I believe Trump would not have even been within striking distance of Clinton on Election Day." ...
Three states where Trump won by very close margins—margins significantly less than the number of votes cast for third party candidates in those states—gave him an electoral college majority. Mayer writes that if only 12% of these third-party voters "were persuaded by Russian propaganda—based on hacked Clinton-campaign analytics—not to vote for Clinton", this would have been enough to win the election for Trump. Political scientist Kathleen Hall Jamieson, in a detailed forensic analysis concludes that Russian trolls and hackers persuaded enough Americans "to either vote a certain way or not vote at all", thus impacting election results. Specifically, Jamieson argues that two events that caused a drop in intention to vote for Clinton reported to pollsters can be traced to Russian work: the publicizing of excerpts of speeches by Clinton made to investment banks for high fees stolen from campaign emails during the presidential debates, and the effect of Russian disinformation on FBI head Comey's public denunciation of Clinton's actions as "extremely careless" (see above).
That last one is a pretty big one. Reportedly James Comey's actions shortly before the election was influenced by Russian disinformation (The Washington Post, The New Yorker). The highly unusual actions by Comey that followed gave that partisan "investigation" Republicans were running as a smear campaign into Hillary Clinton* a brief appearance of legitimacy right before the election, and is widely attributed to the reason polling shifted so drastically in the final days of the election.
* For those playing along at home, the investigation never found anything of consequence.
The answer to your question is that nobody knows for sure. There were a number of factors that lead to Trump’s EC win. The Comey letter in late October probably played a role . But the effect of the Russian disinformation campaign on the net could have played a role as well . And plain misogyny also likely had an impact . The results were close enough and the variables strong enough that absent any of these we likely would have had President Clinton come 20 January 2021 (or President GenericMaleDemocrat).
Search as I might, I could not find a 'non partisan' study of any credibility on the subject.
'Russian interference' was most seen in a series of FB ads, financed to the tune of around $200k, that were pretty much the standard fringe politics fare... unlikely to have any measurable effect on voting. They also supported Bernie Sanders with FB ads, too.
Russia, as in the government, may or may not have been involved in purloining inside information from the DNC and John Podesta. Still unknown if this was government sponsored effort, or individual - a lot of individual hacking originates in Russia. Since neither the DNC nor Podesta questioned the accuracy of the hacked information, they can be seen as contributors to the Clinton loss by their actions.
The successful phishing attack against John Podesta that caused the release of 44,053 DNC internal emails and 17,761 attachments likely had some effect on the outcome of the election. It led to some embarrassing revelations that were detrimental to the Clinton campaign.
While one can't say how big effect the email release had, I think it's safe to say that the effect was non-zero.
There is in my opinion persuasive evidence indicating that the Russian government was behind the phishing attack. The evidence is summarized in FireEye's reports about APT28 and APT29 (Fancy Bear and Cozy Bear )- two hacker groups with suspected ties to the Russian government:
- APT28: A WINDOW INTO RUSSIA’S CYBER ESPIONAGE OPERATIONS?
- HAMMERTOSS: Stealthy Tactics Define a Russian Cyber Threat Group
APT28 is known to be behind the phishing attack against John Podesta and several other members of Clinton's campaign. The group has also launched attacks against political and military targets in Georgia and Eastern Europe which is consistent with the theory that it is controlled by the Russian government.
FireEye also analyzed the phishing software used and found other signs implicating Russia. The language of the compiler used to compile the software was set to Russian indicating that the developers spoke Russian. Most damning, in my opinion, is that the compilation timestamps almost perfectly matched Russian business hours. Over 96% of the compile timestamps were between Monday and Friday and over 89% were between 08:00 and 18:00 in Moscow Standard Time. This means that developing this phishing software likely was a group of Russians regular job.
Still, even though the evidence points in that direction it is far from certain that Russia was behind the phishing attack.