Hello there!
Here is my OPINION/ interpretation. I may or may not be incorrect.
1). The US shouldn't sell arms (weapons) overseas because it would cause a war, and the US's goal was to stay isolated, hence the term isolationism.
Arms = weapons
Arms = body part
Selling weapons across the to Britain could cause conflicts, which could lead to war.
However, (in the first image), of they didn't sell weapons, they'd remain neutral, therefore avoiding war and its costs.
2). This cartoon MAY be trying to persuade the reader that war isn't always the solution to resolving a conflict, and that isolationism can lead to peace and unity.
Again, this is MY OPINION.
Hope this helped! :)
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