That aside, US electorates has decided to award another term for Trump. FYI at that point Trump is not an unknown dark horse candidate anymore and he even won the popular vote. Last time a GOP president won popular vote was 20 years ago.
So it's very fair to attribute the so called erraticness to what American want in general instead of attributing it to Putin or other non American.
Or that foreign influence campaigns on social media are having a good return on their investment cost.