The 2016 Presidential election raised the specter of foreign intervention in the outcome of the voting. There are two levels of alleged intervention being bandied about, one far more serious but the lesser discussed, and the other far more discussed but less significant. One level is hard-core and the other is soft-core. The hard-core is tangible vote count and report tampering. The soft-core is the spreading of propaganda and mis-information to influence citizens to vote for one candidate (or against the others) or to not vote at all.
One can argue that paying people to influence voters is not really a criminal act even if carried out by a hostile foreign government. After all, once a foreigner passes his message to an American and that American chooses to believe it, the message becomes his no matter from where it originated. The propagation of false and inflammatory messages is currently protected by the 1st amendment to the US Constitution.
On the other hand, tampering with vote counts and reports is a Federal crime regardless of who commits it and may also be treason if committed by an American citizen.
There are many allegations of vote count irregularities taking place in key precincts and states. Many of those irregularities did not constitute the basis of flipping the outcome of the Presidential election. However, there were three or four state outcomes which do suggest that tampering might have played a role in the rise of Donald Trump to the White House. Pennsylvania, Michigan and Wisconsin. Trump won those states by 68236, 11837 and 27257 votes. Choosing those states to look at for irregularities is not 20/20 hindsight not is it sour grapes for Hillary losing. These states were targeted to be numerically flipped after historically voting for Democrat presidential candidates. Anyone seeking to push a candidate would look at those states. These ballot numbers represent 0.09 % of the electorate.
Most of today's politics does not revolve around influencing who a voter should vote for but to influence them to vote against the opposition or not vote at all. There is another set of factors playing into the outcomes of elections. Voter Suppression.
Vote suppressions is a matter of convincing people to not bother the vote because it is a "useless" activity since "both parties are the same". Only the lesser party would cling to that message. Making voting more difficult is another tactic which the "party in power" employs. If you make voting a day long ordeal with hours-long lines, people might stay home the next time. Closing polling places and shortening early voting hours also make the main Election Day more onerous. Purging voter rolls also make it difficult at the last minute for a person to cast a ballot. All of these tactics while maybe legal are immoral and counter to the Constitution. It is highly suspicious that all legal vote suppression targets geographic regions where the residents are most likely to vote for Democrats.
And let's not even get started on Gerrymandering of districts to position Republicans in state legislatures where the other voting rules are formulated and promulgated.
Since recent election have "razor-thin" margins it is far too easy to manipulate a few vote counts and flip an entire election. One doesn't need to compromise every voting machine in a state, just the ones that are projected to be key in the election.
Conspiracies to flip elections do not need a lot of conspirators. A reverse Engineering of the process shows where to apply assets. One doesn't need to compromise voting machines when the people who do the reporting are part of the conspiracy. Complicity is also a factor even when the people are not part of the actual plan. When tampered results are certified and recounts denied, the people who do that are indeed complicit but not guilty of conspiracy.
In the 2000 election of George W. Bush ultimately 537 votes in Florida and the Supreme Court set the results. The Florida Governor and the Florida Courts made it all but impossible to get a final recount completed.
The 2016 election has not been adequately challenged in courts. There has been no comprehensive analysis of the results to demonstrate the veracity of the counts. There is however ample evidence that some level of Russian tampering took place and might have tipped the election in favor of a Republican Administration.
One must keep in mind that if the election was tampered with and flipped, both Trump and Pence were illegally put into office. Every cabinet appoint is tainted. Every Judiciary appointment is illegitimate. Every Executive Order and Presidential Directive is suspect to being promulgated to the benefit of the foreign money. America is being turned into "Tuna!" as presented in the concept of It's All Tuna!