[xab31]

The problem is that if you communicate to the public at the level of normal scientific certainty -- with all the methodological and statistical caveats -- it's very hard to generate the moral authority needed to push sweeping mandates on a population.

Political and scientific leaders knew this, and they made a decision to exaggerate the level of confidence they had or should have had in several of these matters. No one seriously expected leadership to have complete knowledge from day 1, but that's not the criticism. Nor is the criticism that facts change on the ground in fast-moving situations. Of course they do.

The criticism is that they knowingly overstated their factual case at the time so that they could implement their chosen strategies, even to the point of suppressing legitimate scientific dissent, and are now unconvincingly trying to use "facts on the ground change", "science learns over time", and "of course we couldn't have been expected to know everything" as excuses for those decisions.

If you're making very confident policy-guiding assertions to the public on behalf of Science (TM), and when you're right, it's evidence of how great Science is, and when you're wrong, it's because Science is a process of continual revision and uncertain information, that creates a bit of moral hazard. It works internally in science, where there are no consequences for being wrong other than wasted time, but not in the real world where there are real consequences for being wrong.