I couldn't resist this one; I really did laugh out loud when I saw it. The first questions most people ask upon learning I'm a vegetarian (and occasional vegan) is "how do you get protein." I think this answers it quite well:
Now to get a bit serious: Americans do not suffer from protein deficiency. When you see children in places like Haiti with red-tinted hair and distended bellies? THAT is a protein deficiency. Americans? We have an animal protein excess which leads to chronic conditions such as cardio-vascular disease. We've turned meat into the centerpiece of our meals; instead, produce and whole grains should be. So, don't forget: plants have protein.