Fortunately for America and the world it looks like Hillary Clinton is going to win the election. Trump is still keeping things somewhat close which to me is morbidly horrifying. Normally it doesn't matter that much who is president, there are a number of checks and pressures that tend to keep policies moderate and US grand strategy similar. Sometimes there are exceptions like the Iraq war under George W. Bush's presidency which probably would not have happened under Al Gore. That said, Donald Trump is the type of president who would test the limits of those checks and restraints.
First, we have to put things into perspective. There is not a mechanism that resolves the gridlock between the legislative and executive branches. This is a flaw in the US system and we are fortunate to not have ended up like Latin American democracies. Trump's style and ideology would take the gridlock to a new level and set an even higher precedent on an imperial presidency.
This is a good Vox explanational video on Trump's nationalist ideology:
In addition, the area a president can act with the fewest restraints in dealing with foreign policy. Currently the liberal world order is under a tremendous amount of strain by the rise of China and the rise of the rest. The best strategy for the United States to guide this transition phase would be a relentless focus on norms, rules, and enforcing those rules. Instead, the US has acted in its own interest, undermining its own authority. Trump's foreign policy strategy at a time of uncertainty would have devastating consequences.
Stay tuned on Tuesday for the final outcome and let's hope that America will live to see another day.