Power
The stats are pretty staggering: there are over 210,000,000 licensed drivers in America and in 2013, 86% of them commuted to work by driving or carpooling (source).
Therefore, a lot of people rely on highways to go to work, school, and wherever else they need to go in order to live their daily lives. You can derive a great deal of power in knowing that your job is one of the pillars keeping America running.
In the day-to-day tasks of the career itself, you won't have a whole lot of immediate power. Starting out, you'll report to your lead crew member who'll instruct you on what needs to be done every day. You won't have much freedom to make decisions. It's pretty much a get in and do your job situation.
But, keep in mind that whatever task you accomplish in a day helps to keep the highways safe and usable. You're the best line of defense against potholes, blind curves, and uneven pavement.