Ummmm....I don't support the smuggling of people, but killing him is just sad. This is suppose to be the greatest country in the world, so should it be of any surprise people sneaking to come here? Reading that made me think of Harriet Tubman. My grandmother used to say you can be 100% right and 100% wrong all at the same time.
Sure it's no surprise, but that doesn't make it right in any way, shape, or form. What the kid was doing will always be 100% wrong and what the agent did will always be 100% right.
Immigration laws and quotas were enacted for a reason: if anyone could just come anytime they chose, the economy would start to degrade and the cultural 'melting pot' created would start to form lumps in it. This is exactly what has occurred. Even worse, there is no record of the illegals who are entering the country, and, big brother mentalities aside, there does need to be information regarding population in order for the government agencies to function properly and be staffed appropriately. In ideal circumstances, there wouldn't be a problem with just letting everyone come and go as they pleased, but the reality is that there are countless number of factors to take into account (population growth, crime, economy, etc... each with their own subsets of factors, those with their own subsets of factors, etc...) that require immigration restrictions for manageability and practicality purposes.
The bottom line is that this kid broke laws necessary to ensure our country doesn't crumble into ruins, and has done so enough times to be on a federal 'Most Wanted' list. Additionally, he and those he chose to illegally smuggle over were being covered by a group of people throwing rocks across to border in attempts to harm a U.S. federal agent. The only regret I feel is that the agent was only able to kill the 15 year old and arrest one member of his human contraband, instead of being able to get them all through either an arrest or a bullet.