If Ruth Bader Ginsburg really cares about the causes she’s fought for, she should retire. Now.

The liberal justice made a bit of news this week by not only saying that she had no intention of retiring from the Supreme Court this year, but that she’s not planning on a strategic retirement any time soon:

She has previously said she wanted her tenure to at least match the nearly 23 years of Justice Louis Brandeis, which would get her to April 2016, and said she had a new “model” in Justice Stevens, who retired at age 90 after nearly 35 years on the bench.

She’s 80 now, so if what she said is for real — and of course there’s no way of knowing how well such public statements track her actual thinking — she’s planning to stick around not only through Barack Obama’s second term, but two presidential terms beyond that.

She says that being a Supreme Court justice is “the best job in the world for a lawyer.” I’m sure that’s true! But it’s also not unusual in politics to be squeezed between what’s best for oneself, narrowly speaking, and what’s best for the causes one cares about.

As I’ve argued before, now is the time. Democrats hold 54 seats in the Senate (and will probably move back to 55 in the fall), but the odds are strong that Republicans will hold more seats after the 2014 elections. Obama isn’t at his peak popularity, but there’s probably more risk going forward. Basically, right now, Obama probably has more freedom to get a replacement confirmed who Ginsburg would be very happy with than he’ll ever have again.

It’s not just her. Justice Stephen Breyer will be 75 in August, meaning that he might have difficulty surviving whoever succeeds Obama.

Breyer was nominated in 1994, Ginsburg in 1993. It’s a great gig — but 20 years is a very good run. Indeed, those who advocate limited terms for Supreme Court Justices generally have picked 18 years as a reasonable term in office. The reality of the court, and the parties, these days is that Ginsburg and Breyer should know that a Justice selected by President Rubio or President Jindal or President Cruz is going to produce a very different nation than one selected by Barack Obama.

That’s why partisan strategic retirements have become far more common recently. And if either Breyer or Ginsburg takes that route, sooner is much better than later.