The Democrats are making President Obama’s 49th birthday on Wednesday a big deal. Our society uses birthdays to define responsibility and adulthood. The Constitution provides that a person is not mature enough to be President unless he or she is 35 years old. You have to be at least 30 to serve in the U.S. Senate and at least 25 to serve in the House of Representatives. If you are 18 years old, you can vote in federal or state elections, according to the 26th Amendment, but states or Congress could make the voting age even lower.

We know the President was old enough to host a “beer” summit at the White House, and we know he sometimes sneaks a cigarette. Under the law he is old enough and mature enough to take those risks with his health and the risks to society.

How old would President Obama have to be in order to be responsible enough to smoke marijuana? 49? 35 years old? Old enough to be a Senator or a Member of Congress? Old enough to drink? Old enough to vote? Marijuana is safer than alcohol and tobacco. That is not in question. As a society, we presume that if you are 21 years old you are mature enough to use alcohol responsibly. We only punish alcohol drinkers who are actually irresponsible.

Proposition 19 is on the November 2, 2010 ballot in California. It would let adults who are 21 use marijuana and grow their own. Isn’t that reasonable? Isn’t it time to Just Say Now?

Mr. President, happy birthday. Aren’t you old enough to smoke marijuana? How old should the rest of us be to take responsibility for our marijuana use? If we are old enough to drink, aren’t we old enough to be given the responsibility to use marijuana?

Eric E. Sterling, age 60, an attorney and former counsel to the U.S. House Judiciary Committee, is on the advisory board of Justsaynow.com.