Rehoboth Beach, Delaware CNN — In the end, President Joe Biden exited the political stage in isolation. After weeks of fighting for his political life – insisting he wasn’t going anywhere following a disastrous debate performance – the president’s about-face did not come in an Oval Office address or a speech on the campaign trail. Instead, it came in letter posted to social media as he recovered from Covid-19 at his beach house in Delaware. It was a low-key way to reveal one of the most historic decisions in modern American politics, but time was not on Biden’s side to...