USA is one of the implementation of the presidential system of the country. From the first president, Washington to President Obama, a total of 44, but only 43 presidents, because the twenty-second and twenty-fourth president, was the same one. USA previous 43 presidents of the six isLawyerBirth, three had served in the armed forces.

     In 2007 I was in the bookstore to see one of the USA presidents biography, open opened the book at random, all most of these "President" is associated with "lawyer".

    
The first president, George Washington: the land surveyor, soldier
The second president, John Adams: Lawyer
The third president, Thomas Jefferson: Lawyer
The fourth president, James Madison: Lawyer
The fifth president, James Monroe: Soldier
The sixth president, John Quincy Adams: lawyer, Professor
The seventh president, Andrew Jackson: soldier, lawyer, judge
The eighth president, Martin Van Buren: lawyer, judge
The ninth president, William Henry Harrison: Soldier
The tenth president, John Taylor: Lawyer
The eleventh president, James Knox Polk: Lawyer
The twelfth president, Zachary Taylor: Soldier
The thirteenth president, Millard Filmore: Lawyer
The fourteenth president, Franklin lawyer
The fifteenth president, James Buchanan: Lawyer
The sixteenth president, Abraham Lincoln: the salesman, the crew, the land surveyor, postmaster, lawyer
The seventeenth president, Andrew Johnson: the tailor (who was the first president USA neither a lawyer, not military)
The eighteenth president, Ulysses Simpson Grant: Soldier
The nineteenth president, Lasse Forde PACHA Hayes: lawyers, prosecutors, soldiers
The twentieth president, James Abram Garfield: lawyer, Professor (Politics after the civil war was to join the army)
The twenty-first president, teacher, lawyer, judge advocate
The twenty-second president, Grover Cleveland: teachers, lawyers, prosecutors
The twenty-third president, Benjamin Harrison: lawyers, prosecutors, soldiers
The twenty-fourth president, Grover Cleveland: (and twenty-second president, to the same person)
The twenty-fifth president, William Mickinley: the teacher, soldier, lawyer, attorney
The twenty-sixth president, Theodore Roosevelt: no (22 at Columbia University School of law, the following year dropped out of college to politics)
The twenty-seventh president, William Haward Taft: lawyers, judges, prosecutors, Dean
The twenty-eighth president, Woodrow Wilson: lawyer, Professor, University President
The twenty-ninth president Warren Harding, Jiamalier: Journalist
The thirtieth president, Carle asked Coolidge: lawyer, prosecutor
The thirty-first president, Herbert Clark Hoover: Engineer
The thirty-second President, Franklin Roosevelt: mother's lawyer
The thirty-third president, Harry Truman: clerk, the grocer, the judge
The thirty-fourth president, Dwight David Eisenhower: Soldier
The thirty-fifth president, John Fegirel Kennedy: writer, journalist
The thirty-sixth president, Layton Sarbanes Johnson: Teacher
The thirty-seventh president, Richard Nixon: Lawyer
The thirty-eighth president, Gerald Ford: Lawyer
The thirty-ninth president, Jimmy Carter: the farmer
The fortieth president, Ronald Reagan: the announcer, actor, soldier
The forty-first president, George Herbert, Walker Bush: soldier, businessman
The forty-second president, William Jefferson Clinton: Professor, lawyer (for trousers chain door events has been suspended for the qualification as a lawyer for five years)
The forty-third president, George Walker Bush: soldier, businessman
The forty-fourth president, Obama, became the first black president American history; the lawyer, Senator; (state, Congress)
 These data leave us what???