“Age doesn’t matter” is the all-but-official re-election slogan of Dianne Feinstein.

Of course, that’s self-serving when you’re in your ninth decade. But, Senator, if you want to show people you really mean what you say about age, there’s a smart way to show it:

Give 16 year olds the right to vote.

In California, that would require legislation. Nationally, it would require a constitutional amendment. Feinstein should propose both. Giving the vote to 16 year olds is a smart and righteous idea for a whole host of reasons.

Among them: turnout among young voters has been falling, as they feel disconnected from the process. But one factor is the perception is that voting and politics are for the old and privileged. (Where would they get that idea?)

Worse still, 18 has turned out to be a bad age to have people start voting, because that is a time of transition – when people finish high school and leave home, for college or work or the military. Away from their family, they are much less likely to be connected to community and to vote. When you’re 16, you can have family and a school community reinforcing voting, which makes it more likely that voting will become a habit.

Is 16 old enough to vote? Heck yes. Research shows that 16 and 17 year olds are just as informed and engaged as older voters. At that age, you can drive, work full-time, and pay taxes. So why not vote?

Indeed, American society needs such voters. As the country ages rapidly, and people live longer, the preferences of the old have come to dominate our society, and tilted investment against the young and the new. The vote for 16 year olds won’t end that bias, but it will counter it, at least a little bit.

The idea isn’t new. It’s been debated in California, and the cities of Takoma Park and Hyattsville, Maryland, have done it, with positive results.

But the idea needs older champions. Why not the oldest member of the U.S. Senate?