In real war, you don't get to call in helicopters unless you are highly ranked and know about it at the beginning of the mission.
In real war, you don't get a radar and a spy plane.
In real war, you have an 80-pound pack on your back and an at least 10-pound gun.
In real war, headshots kill people in one shot.
In real war, bodyshots will likely kill you in one shot.
In real war, second chance ability is a joke.
In real war, you hide behind cover, not run out and get killed, not respawn. You fear for your life and the lives of your friends around you.
In real war, you can't not make any footstep noise.
In real war, reloading is more technical than Tapping X.
In real war, there are no noobs and no experts, just you and your enemy.
In real war, there are objectives.
In real war, "dolphin diving" will likely break your rib cage or kill you.
In real war, there are only about 4 rocket launchers per 300 men.
In real war, you can't flush out a sniper squad with grenades.