Pros
A one-of-a-kind job, especially if the nation is in a period of conflict and you are actively employing your training and skills. The job satisfies a particular sense of adventure and call to action that sweep young men. Opportunities for career development, be it schools or for volunteer special operations units, is very high with the infantryman military occupational specialty (MOS), rivaled only by certain intelligence-related MOS's as far as opportunity goes. The skills and mentality developed in the infantryman profession provide a solid and grounded disciplinary base for life outside the military, and the friendships formed (especially those forged by the experiences of combat) in will last until the end of your lifetime.
Cons
Restrictions imposed by doctrines guided by political correctness can sometimes be suffocating and detriment greatly to performing soldierly duties. The military lifestyle is a time, energy, and sometimes emotion sink, and familial bonds can be damaged or outright severed if one is poor with managing any of the above. Leading off this, being an infantryman is commonly and widely accepted to be a "single man's game." A meek and timid personality, especially in a testosterone-fueled environment of the infantry platoon, can work against you.