There are screams in the streets (edited)

[dukealien]

There are screams in the streets of what is right  Why no period here (and elsewhere)?
Voices lift in one impassioned song.  perhaps "up" versus "in" but, as is, escapes "lift" voices, which is overused.  Good.
Pick up your weapon and join in the fight.  Since this sentence is imperative, it should end with an exclamation point.

The masses stand, a staggering sight
If ev’ryone's right then is everyone wrong?  Not sure what was intended with the apostrophes.  Do you mean, if each one's right then everyone's wrong?
There are screams in the streets of what is right  A little clunky with "there are" - how about "screams (verb) (in?) the streets?"

The military shows its strength and might.  Since "strength" and "might" are much the same, perhaps a descriptive replacement for one - "serried might," for example
The marching lines are drawn and standing strong  perhaps "its" instead of "The?"
Pick up your weapon and join in the fight  Again, exclamation point here

Marching and chanting from dusk until light  good cliche avoidance
Flowing like a river rushing headstrong  leveraging "headstrong" instead of "headlong" - good
There are screams in the streets of what is right  again, "there are" is weak - what active verb can move the screams?

For all the clamor that can't be put to light  "put to light" is good cliche avoidance (for "brought"), but need better - "touched with light?"
Sides clash with each other's prong.
Pick up your weapon and join in the fight.

Will you stand quiet and alone tonight,
Or will you walk the path laid out long?  Like  "prong," a stretch to rhyme.  "walk hard paths and long" is archaic...
There are screams in the streets of what is right 
Pick up your weapon and join in the fight

*I specifically need help with line #14.

In moderate critique, don't take all the above suggestions too seriously.    One hint learned from computer programming:  if the rhyme is not coming, or the one that comes doesn't work, the problem likely is not right there - it's somewhere earlier in the project.  Check for places where the word that doesn't fit here could exchange with its (rhyme) counterpart above, or the thought of which it's a part could change direction and make the annoying word work - or another that doesn't as it stands.