One other thing to look at is how infant mortality is calculated. The U.S. makes many heroic efforts to save premature and otherwise ill babies. If they take even one breath and then don’t survive they are counted as a live birth with a zero lifespan bringing down the average. Many countries will count those as the same as a stillbirth and not include them in mortality statistics which increases their average.
Exactly right.
In addition to your excellent point, US stats also include all the illegals who have come here with exotic diseases that they pass around. Or non-exotic diseases. There is a huge outbreak of measles among Somalis in the US who refused to get vaccinated.
I’m not entirely sure, but it may also include those who come here for treatment of end stage diseases.