Lets try and not turn this into the blame game or politics. We have enough threads for that. If you don't have the will power probably best you don't post.
One of the first major things that was done was to stop most flights from China.
This was the logical and common sense thing to do.
What we didn't know at the time is that it already spread to Europe. Stopping those flights would have had a much bigger impact.
Next came social distancing and lockdowns.
Again common sense and logical things to do.
Are missing something that would have helped us more?