In the second stanza, kipling lists some “positives” that colonization might bring. what are they?

Kipling, like many individuals in his generation, viewed colonialism as a positive  force. Kipling believed that it was a facilitator of civilization, it provided important moral and educational benefits and was the responsibility of more advanced nations to bestow on less advanced nations.

the united states broke it's neutrality was the constant german sinking of trading vessels resulting in the loss of lives, one example would be the lusitania.