There are also terrible ways to end pandemics (and they all end)
I'm not sure I follow the argument about bad new variants arising especially in immuno-compromised individuals. Let's say that's right, reasonably. Wouldn't the number of those cases still scale approximately with the total number of infections? In that case, the selfish argument would still be correct. Since the people who it might reach probably exist, it seems strange to make a shaky case against it. It's not like it contradicts the argument from basic decency.
I think this is not about selfishness; it's about how far you (think you) have come with vaccinating your own country.
I'm not sure if it has fully filtered through into American society that the US has enough (non-AZ) jabs for every of its citizens. (In fact I'm keeping up with US news and I only learnt of this from you -- and even then I'm a tad doubtful. You are talking about doses in reserve or doses ordered? Is this sourced from the FDA, the CDC, the companies or the Biden admin?)
As a German, I was somewhat aggravated to read your previous post (for no fault of yours) -- Merkel and various EU officials have started talking of vaccinating developing countries before Germany even had 5% of its doses administered; very few places in the EU are anywhere near the maturity of their vaccine rollout where this kind of discussion has a chance of attracting anything besides irritation among voters. And unlike the US, we don't have a second-choice vaccine that we know for sure we cannot use. If I was in the US and knew that it's just a matter of money, I'd be more sympathetic to sharing around.
I believe that this argument doesn't sufficiently account for how political leaders of countries capable of mass producing vaccines will act. First the national leader will take care of their own countrymen. Next they will take care of their neighbors. After that decisions will get more complicated having to balance the advantages of helping allies with the need to bring the pandemic to an end. As long as a country can produce vaccines, national leaders will want to distribute them, if for no other reason than to obviate the risk what may happen if the virus is allowed to evolve.
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