Actually, "putting the oxygen mask on yourself" would be the equivalent to vaccinating your medical staff, not your whole friggin country.

The US and UK don't fare much worse than the rest of the EU, per capita, do they?

USA+ UK = 34 million cases, EU=24 million cases.

The biggest problem with vaccine mercantilism is if we don't rationally share the vaccine, the vaccine technology and means of production, then the fact we vaccinated 100% of one country will be useless in 2 years with all the variants mutating in less fortunate countries.