For climate change, we need to demonstrate the ability to proactively avoid a creeping catastrophe that will occur in the medium-long term, where the harm may not happen to current decision makers, but will instead happen to other people who don't get a vote in the decision today, and isn't media worthy since nothing is really changing ("outlook remains bleak").
1. The most in-depth writeup I've found reports a fatality rate of ~5x higher after more widespread testing: https://www.economist.com/graphic-detail/2020/03/12/how-dead...
However, I very much doubt that this is the calculation that went through very many people's heads, say, 3 weeks ago.
I think proof of this is that in all places that have substantial outbreaks, containment measures are getting heavier and heavier with increasing numbers of cases. If that's what you were going to do anyway, then the sum cost (in money, time, human effort) would have been lower if you had started earlier. This is because exponential growth with a factor of 1.33 is still manageable if you have 10 cases, but turns into an overwhelming tsunami if you have 10000.
I disagree. Shutting down major portions of the economy, and the resultant economic damage, would have been quite severe regardless of when it was implemented. Not saying there wouldn't have been less panic, but broad quarantines would have caused a lot of panic in any case.
I listened to Richard Mueller's "Physics for Future Presidents" podcast course, and he presents an interesting conundrum: say you're the mayor of a small town, and a seismologist approaches you with a report of a 15% chance of a devastating earthquake next Tuesday, recommending a citywide evacuation. Being a responsible mayor, you do so, despite the cost and displeasure of your constituents. On Tuesday, no earthquake occurs, and the town repopulates. This happens ten more times over several years, and still no earthquakes (after all, each occurrence is only a 15% chance). Sure enough, another Tuesday, another 15% prediction, and citizens are getting frustrated. As the mayor: do you order another evacuation, especially if it's costing you significant resources and political capital? How can you tell the difference between getting lucky on the numbers, and a bad seismologist? Even if the data is accurate, how do you not succumb to the temptation to play the odds?
If there's any silver lining to our failure to prevent the pandemic, it's that maybe we'll take the problem more seriously on the next pandemic, perhaps one with a much higher fatality rate.
It's easy to mock anti-vaxxers, climate denialists, et al; while an honest inquiry leaves room for nuance, those issues seem to have definitive answers, where reality correlates closely with the so-called consensus. But at the same time, the knee-jerk anti-science reactions should be viewed through a lens of general declining social trust in institutions. Even though those particular issues may be the wrong fields of combat, there's a subconscious sense in which everyday people feel lied to for decades by "experts". Now we're stuck in a boy-who-cried-wolf situation, where the actual experts who are honest brokers and have their shit together aren't being taken seriously. Trust is hard-won and easily lost, and there are massive downstream effects to corruption in truth-finding/sense-making institutions.
To your 15% chance of disaster example from your other comment: I think what you need is a population where a large fraction of people understand where those 15% come from.
Edit: I also want to point out that I didn't find your examples that convincing. Bloodletting was a seriously long time ago, and is unlikely to affect anyone today. Iraq was a purely political issue, and didn't have a scientific angle.
Coronavirus cases have been growing stably and predictably for weeks. Epidemiologists (and not only they) saw it coming. No panic would have been necessary if calm, decisive action had been taken early on. But somehow the panic seems to be necessary. Normalcy bias is real.
These past weeks have been really instructive about collective human behavior, and have me really worried about our ability as a species to address climate change.