Lines 408-416: what does the repetition of the phrase "this is not just"
emphasize? speech on the vietnam war,1967 by martin luther king jr

The repetition of the phrase "This is not just" emphasizes the exploitative actions and arrogant attitude of the Western world.

Explanation:

Martin Luther King Jr makes use of the literary device of Anaphora by repeating the phrase "This is not just", He intends to get the audience's attention into the social conflicts that people have to face every day in their lives due to the exploitative actions and arrogant attitude of the Western world.

a complex sentence consists of an independent clause and one or more dependent clauses.  

to write complex sentences, we must use subordinating conjunctions.  

all the complex sentences begin with a subordinating conjunction and when it occurs, a comma must be place at the end of the dependent clause. on the contrary, if the sentence begins with an independent clause, then no comma is used.

after  

although  

as  

because  

before  

if  

since  

when  

for example,  

after she won the competition, she became very popular.  

although my father was hurt, he continued fighting for his rights.  

as all of you got a ten, you will be able to leave early today.  

before he went to the war, he asked his parents to bless him.  

if it is cold, i won’t go out.  

since you didn’t bring the homework, you will get low grades.  

when it is hot in the town, everyone goes to the beach.  

(you didn't attach a copy of the poem, but i'm answering as best as i can)

since a simile compares two unlike things using like or as, it kind of gives an item the ability to do something it can't.

example: "the player was like a tiger on the field"

in this sentence, the simile conveys the idea that the player was fast and strong, like a tiger.