You have to remember that, if the other country has a smaller population than the US does, then the other country is NOT "experiencing an outbreak of this scale".
Only China and India have populations larger than the USA, so that means that the only countries that could possibly be "experiencing an outbreak of this scale" would be China and India. India has only reported around 5,000 cases, so that means that India is NOT "experiencing an outbreak of this scale". China, although only reporting around 81,000 cases isn't even close to the 337,000 in the US, so that means that China is NOT "experiencing an outbreak of this scale".
Therefore, since there are NO OTHER COUNTRIES that are "experiencing an outbreak of this scale" that means that NO OTHER COUNTRY is doing a better job of coping with "an outbreak of this scale", and that means that Mr. Trump is - obviously - out performing EVERY OTHER LEADER and the US is - obviously - out performing EVERY OTHER COUNTRY.
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