Donald Trump’s age is showing! On Saturday, June 15, a video went viral of the former president looking visibly cautious as he walked down the stairs when exiting his jet. “Look how intensely focused he is on not screwing this up because this is so important to him. Staring down the whole time while gripping that railing. Then you can see how proud he is of his accomplishment at the bottom,” one X user penned alongside the clip of the 78-year-old in his classic navy suit and red tie. In response to the footage, trolls mocked Trump, who is running for president in 2024. “It’s hard to do stairs …