President Barack Obama's second term is reaching its terminus, with the 2016 presidential election just weeks away. After eight years of serving as President of the United States, he has no doubt learn an incredible amount, and if President Obama could time travel he would probably impart a lot of much-needed wisdom on his younger self.
Jimmy Fallon and The Tonight Show gave Obama that exact opportunity, setting up an imaginary tête-à-tête between his 2016 self and the newly elected President Barack Obama of 2009, shortly after he'd been sworn in as Commander-in-Chief.
Besides the revelation that Obama has aged 20 years in the last eight years, watching this video will reveal all of the most important things about being president, such as the importance of having some Purell hand sanitizer at the ready and that "falling short of the ideal" is inevitable. There are probably a few other bits of knowledge he'd impart on his former self if he could, like what's going to happen in the 2016 presidential election, but those bits might not be suitable for TV.