In a season when the dark forces of fundamentalism dream of a world in which everyone thinks alike, dresses alike and believes the same thing, it’s good to embrace a holiday that celebrates oddity, irreverence and nonconformity.

That’s why Mardi Gras is especially welcome this year. Our troubled planet needs Carnival now more than ever.

Mardi Gras is French, of course, for Fat Tuesday, although no one who’s lived in south Louisiana for any length of time needs a translation. Our kinship with France goes back to our founding.

That’s why this winter’s terrorist attack against a Paris magazine resonated so strongly in Louisiana. Our cultural cousins were under assault for daring to flout convention and make a joke, two things we love to do in this state. To think that thugs would kill someone for that made us cringe.

Sadly, that brand of extremism is becoming all too common these days. News of beheadings and burnings abroad tell us this is so.

But Carnival champions a different vision of human possibility. Mardi Gras reminds us that humanity thrives in variety, not orthodoxy; in questioning authority, not mindlessly imposing it; and in laughter, not bitterness.

And there is a reason, too, that Mardi Gras unfolds outdoors, along the parade routes, in patios and on balconies. Carnival reminds us that we’re at our best when we’re open to the world.

Mardi Gras is our ageless answer to those who believe in the bankrupt idea of society as a fortress. Carnival tells us that life is not a prison, but a parade float — a procession offering the gaudiest of gifts to those also willing to open themselves to strangers, shoot up their hands and shamelessly beg for beads.

It is right that Mardi Gras should celebrate oddity because America grew from oddballs. We began as a nation of immigrants who started new lives here because they couldn’t fit in where they were.

Mardi Gras isn’t a national holiday, although perhaps, in some ideal world, it would be. There’s a puritanical streak in our national life, too — a leavening influence that’s prevented Carnival from gaining a foothold across the country.

Fine by us. Let’s face it: Bacchus in Boston or Rex in Racine would somehow, we suspect, not be Carnival at all.

Mardi Gras is Louisiana’s special gift to the world.

Laissez les bon temps rouler.