In retrospect the reboot Trek films seem to have a theme going on:
Nero, Marcus, Khan and Krall are all throwbacks of previous eras or ways of thinking in which being mightier is better, and using violence to pursue your aims
Not sure if this is on purpose, or if this is an unintentional theme of the reboots.
Nero was so obsessed with what happened to his world in the Prime universe, that he couldn't be reasoned with or talked down, wanting to destroy everyone.
Admiral Marcus thought that the best way to deal with the Klingons was via a preemptive strike, subterfuge, and killing of innocent lives.
Khan is a conqueror from the 20th century, bent on conquest, revenge, and saving his people.
And now, Krall, someone from a place that knows strife and violence, and thinks the Federation is wrong for trying to have peace and unity, because:
Spoiler