Brock Lesnar has been called many things. He's worn many mantles throughout his career. Currently, he's called Champion. Before that, he was called an MMA freakshow. During his pro-wrestling days, he was often called The Next Big Thing. As an amateur wrestler, he wore the title of All-American.
But Lesnar's more than just All-American. Lesnar, and everything about him, IS America. Don't understand? Look at the parallels.
If you look at the world's most storied civilizations, who do you think of? China, Egypt, Japan, Mesopotamia, India, Rome and Greece are just a few of the world's great kingdoms. And almost without exceptions, these great powers have been around for thousands of years in some form or another. America is different. America is currently the most powerful country in the world, but America's existed for less than 250 years. Compared to other great civilizations, America's track record is lacking.
Brock Lesnar is no different. The best and brightest heavyweights in the history of MMA all have long, storied careers. Fighters such as Fedor, Nogueira, and Couture have been in dozens of wars and fought for years and years. But the current #1 HW on the planet doesn't have that long track record. He's got 6 fights. Brock Lesnar is America: Young, new, and seemingly out of nowhere the most powerful force on the planet.
Lesnar is the most polarizing MMA fighter in the world today. He may be one of the most (if not the most) polarizing championship-level fighter in MMA history. Most fans either love him or hate him. Many MMA hardcores hate his pro-wrestling background. They hate his bravado. They hate that his athleticism seems to give him an edge over every fighter he faces. Other fans love him. They love the bravado and the theatrics. They see him as the next step in the evolution of the modern mixed martial artist. Many professional wrestling fans followed him to the UFC, and for every detractor he's got a loyal supporter. In much the same way, America seems to be a love-hate country.
Isolationism: For much of United States history, America has been content to sit on its own continent, never bothering to take note of the rest of the world. Despite a few attempts at colonialism and recent wars, for most of America's lifespan, foreign policy could be summed up as "Leave Us Alone". Brock chooses to live in the middle of nowhere in Minnesota. He doesn't do media. He hates promotion. Like America, he can kick ass when he's riled up. But mostly he just wants to be left alone.
Size: In America, bigger is better. This is the land of the giant Hummer, the Super-Sized Deluxe Meal. Brock Lesnar is the biggest, strongest, most athletic man to ever fight at 265 pounds. If MMA fighters were manufactured like cars in America, the early model wrestlers would have looked like Randy Couture, Don Frye, and Mark Coleman. What would any good American corporation say about making the next generation of fighters? "To hell with it, let's build 'em BIGGER". You couldn't make a more American fighter than a man who takes everything good about the previous legends and puts it in a frame that seems nearly twice as big.
A polarizing figure who sprang from (relatively) out of nowhere, and quickly became the most powerful force in the world. A brash figure, prone to public missteps, with an excellent record when the going gets tough. Full of bravado, but with a deep desire to be left alone. A figurative and literal giant. Brock Lesnar doesn't just coincide with one or two American traits. I think in many senses, there may not be another fighter alive who represents so perfectly everything America is.