We Americans want it all, don’t we?

Food that’s cheap but delicious. Airports that are safe yet convenient. Presidents who are smart and still say damned charming things like “misunderestimated.”

But time and again, we find we can’t have it both ways.

Just look at our reaction to the plight of Lisa Nowak, the NASA astronaut who lost her boys’ club cool last week and attacked a romantic rival with pepper spray.

While wearing a wig.

And, um, a diaper.

Police are calling it a love triangle: Nowak, a decorated Navy engineer who flew on the space shuttle Discovery in July, drove 12 hours from Houston to Orlando to confront Air Force Capt. Colleen Shipman, with whom she was competing for the affections of astronaut Bill Oefelein. She wore adult diapers so she wouldn’t have to pull over at rest stops, disguised herself in a wig and trench coat, followed Shipman to her car and then sprayed her in the eyes with pepper spray before her victim escaped and got help.

Police found a BB gun in Nowak’s car, along with a four-inch folding knife, gleaming steel mallet, latex gloves, four feet of rubber tubing, garbage bags and $600 cash.

Unless she planned to construct a crude getaway parachute — or a sophisticated diaper-disposal system — it all looks bad for Nowak.

Now the 43-year-old mother of three is facing charges of attempted murder while America blithely lampoons her as a wingnut. Headlines like “Lust in Space” and “Dark Side of the Loon” topped the news story. Jay Leno joked about the aerospace engineer being the worst sort of flight risk and David Letterman offered the “Top Ten Signs an Astronaut Is Trying to Kill You.”

All of which is funny, indeed, and I’m not saying Nowak’s sane. NASA’s psychological screenings notwithstanding, I’d rather wander Fresno with Anne Heche’s alien ego than sip Tang with this mallet-wielding galaxy trotter.

But isn’t it hypocritical of us, as a nation, to mock a woman like Nowak for letting her heart guide her actions — when we revile Hillary Clinton for doing just the opposite?

The comparison between Captain Nowak and Senator Clinton may seem strained — one’s running for President and the other, thanks to a court-mandated ankle bracelet, isn’t running anywhere. But both women have attained a rare level of success in grace-under-pressure careers dominated by men. Nowak is known as “Robochick” for operating the space shuttle’s robotic arm. As the less-popular half of “Billary,” Clinton was believed to have undue influence over her husband’s presidency.

And both, now, have seen their professional achievements undermined by amorous entanglements. But if one of them horrifies the nation by hunting down the “other woman,” and the other is labeled “cold-hearted” for sticking with her philandering spouse, there appears to be a double standard at work:

When successful women have our hearts broken, we’re damned if we plot murder, and damned if we don’t.

It’s worth noting that, in love triangles, men come unhinged, too. But no one ever drags their professional life into the discussion. (If wife murderer Scott Peterson was accused of being an unfit pesticide salesman, I stand corrected.)

The hypocrisy points to an important question: How do we want our female leaders — passionate and unpredictable “like a woman,” or controlled and calculated “like a man”?

Would we, deep down, really prefer that women stay home and stop meddling in areas that were once so neatly — so masculinely — defined? Or would we simply rather the nation’s female role models abstain from the messy business of falling in love, so that we can forget they’re sexual beings entirely?

Women are multi-faceted. I love that Nowak’s NASA biography reports her hobbies as skeet shooting and growing African violets. I love how Clinton admits, in her autobiography, that her husband’s infidelity left her “furious” and “gulping for air,” but that she can still somehow manage to not assault Monica Lewinsky in a Florida parking garage.

Ultimately, a woman’s going to pursue that which makes her happiest, and no amount of public scorn is going to stop her.

For what it’s worth, though, I’d rather our next President approach life’s challenges with a poker face than a pocket knife.