The terms are similar to those used during the American Civil War. At that time, southerner meant more than just a person from the southern portion of the U.S. It also conveyed that the person supported the rebellion, slavery, and war with the Union forces. A northerner supported the Union, the freeing of slaves, and the Union army.
When a gang member identifies himself as a Sureño either verbally or by clothing or tattoos, he escalates his position from a mere Latino gang member to a soldier in the service of the murderous Mexican Mafia. This is what kanpol is meant to convey.
When pilli is used to identify an Eme member, it signifies that he's held in high regard. He's considered a noble man or royalty lording over the kanpol (common soldier) army. Initially, the Mexican Mafia's ambition was simply to control the DVI facility. Later, they warred to control the California prison system, and then the federal prison system. Today, they covet control of the southwest and the entire nation. They plan to do with their growing kanpol army.
How do you measure the danger posed by your local Sur 13, South Side, or Sureño gangs? Their level of sophistication will tell you. Talk to them. Do they use the terms pilli or kanpol? Do they identify themselves as a Sureño? Have they tattooed Southside, Sur or Sureño on their body? Are they "piasas" (a person from Mexico) or are they from Central America?
The most dangerous Sureños are hard-core California gang members who have done prison time and have been indoctrinated in the schooling system of their master (pilli). The second type of Sureños are converted local Latino gang members who emulate the Sureño gang style, even if they've never been to California. Some of them are still dedicated enough to act just like kanpol soldiers.