The answer is: An untended garden grows and blooms.
A salutary neglect can be understood as a form of not giving enough attention nor caring for the needs of someone or something and, still, getting good and beneficial results. Which is what the sentence expresses:
<em>"An untended garden"</em> = neglected.
<em>"Grows and blooms"</em> = Good results despite neglection.
I haven’t researched this much, but i do know that there were no beds for the slaves, they were chained to the ground shoulder to shoulder, typically unclothed. a lot would vomit from seasickness, terror, or lack of nutrition, and a good portion of them died before getting to their destination.
There were actually four HUGE causes for WW1, treaties and alliances brought many countries into war, the imperialism of some countries scared other countries, and they were "defending" themselves, there was a lot of weapons stocking, and countries were creating gigantic armies, and that threatened other countries, and then we have plain old nationalism.
The theory that was used to justify claims of racial superiority was <u><em>social Darwinism.</em></u>
Social Darwinism was a group of ideologies that arose in the late 1800s in which Charles Darwin´s theory of evolution by natural selection, was used to justify certain social views.
According to the theory, the weak were diminished while the strong grew in power over the weak.
One of the persons who adopted social Darwinism was Adolf Hitler, who considered that the German master race had grown weak due to the influence of non-Aryans, so he targeted certain groups of people that he considered biologically inferior for extermination such as jews, homosexuals, etc.