The purpose of the Fourteenth Amendment was to abolish slavery and involuntary servitude in the US.
prohibit discrimination based on race, color, or religion.
guarantee citizenship for anyone born or naturalized in the US.
protect “separate but equal” laws in the workplace.

genetics is the study of how dna works, the methodologies defining the new recent technologies allow scientist to have a panoramic view of the entire dna landscape, especially how genomes interact with their environment, including off course, factors outside their organisms.

thus is very possible the existence of both scenarios, where populations of isolated individuals have different genetic traits, and share traits related to genetic mutation, due rats can easily travel overseas using human transport channels. so scientists could get a vast number of data, including human interaction, evolution of rodents, health development, spread of infections, development of new organisms, how genomes evolve in different environments and so on.

to force terrorists groups to stop attacking western targets using massive military force.

you didn't list the options. however, a few communist countries today are: the people's republic of china, north korea, and cuba.