In terms of rollout. UK is the ideal country to be the first: 1. Heavily impacted by Covid-19. 2. Centralised health care system makes it easier to compare results and efficiency. E.g. it's UK which figured out that dexamethasone is efficient against Covid https://www.who.int/news/item/16-06-2020-who-welcomes-prelim... 3. Developed country with great logistics.
Given how short of a time it took to actually develop this thing, could we have drastically sped up this process by maybe being a bit more risky with the trials? At this point ~1.5 million people have died from the virus.
I've really struggled with this knowledge that we've had a vaccine which it turns out is 95% effective for practically the entire course of the pandemic at at this point... and our conservative "moral" process was to let 1.5 million people die while we vet it.