The American Museum of Natural History has a long and honorable tradition of enlightening the world at large with outstanding scientific exhibits and public lectures But now there are agitators waving signs in front of the Museum. They are vilifying a scientifically-engaged trustee, Rebekah Mercer, who helps make these exhibits possible with generous donations. Ms. Mercer’s family foundation also supports politicians the agitators despise, and organizations or scientists with views contrary to their belief in human-caused, catastrophic global warming The signers of this letter include many scientists, with a deep understanding of climate. The case for harm from catastrophic global warming is growing weaker as more is learned about the Earth’s climate system, and about the poor predictive power of computer climate models. The Earth has supported abundant life many times in the geological past when there were much higher levels of carbon dioxide in the atmosphere. It is quite likely that future generations will benefit from the enrichment of Earth’s atmosphere with more carbon dioxide. And there is no doubt that policies advocated by many of the protestors will cause economic harm across the world, especially to those hoping to climb out of poverty It is unlikely that Ms. Mercer and all of the signers would vote for the same political candidates. But all of us urge the Museum trustees not to cave in to this pressure. Make no mistake, the agitators are not defending science from quackery—quite the contrary! They demand that the Museum support a party line, thinly disguised as science.