Why might the cartoonist have represented the US as a life raft?

there isn't a cartoon shown here but in history the US was usually represented as a safe haven for immigrants from other countries. Many places were going through famine, war, suppression, etc. so there were many immigration booms. The cartoonist was probably trying to get more people to move to the US by representing it as the solution or as something that can save struggling people.

Explanation:

uhm I like history

<3

a. people generally need the same amount of physical activity to maintain weight stability.