Napoleon is credited with saying “Every corporal has a Field Marshal’s baton in his knapsack.”

In modern times, it would seem that every Cathedral Prep student has a Grand Marshal’s sash stashed in his book bag.

Tablet Editor, Ed Wilkinson, who graduated from Cathedral Prep, Brooklyn, in 1965, will step out this year as Grand Marshal of the Bay Ridge St. Patrick’s Day Parade on Sunday, March 25. He will join a long green line of Cathedral grads who have led a big parade in honor of Ireland’s patron saint.

For a small school with no military tradition and whose student body marching skills would make a drill sergeant sulk for days in the battalion beer tent, this is indeed a remarkable fallout from a most peace loving curriculum.

The mission of the preparatory seminary is to nourish vocations for the priesthood, a calling that marches to a different drummer and is often sadly out of step with the modern world.

And yet consider how often a Cathedral man has been out front in the line of march when the band strikes up “The Wearing of the Green” or “The Minstrel Boy.’’

William Flynn, Prep class of 1943, a year behind me, is a foremost example of Cathedral grad as front runner. In a silk top hat, clutching a shillelagh, Bill marched up Fifth Ave. in 1996 as Grand Marshal of New York’s St. Patrick’s Day Parade, the largest and oldest in the country.

His tall opera hat, most appropriate for strutting up that canyon of skyscrapers, was collapsible, like the one worn by the Lord Mayor of Dublin. So Bill could tuck it into a bureau drawer, then snap it back in shape again five years later when he stepped out as Grand Marshal of the Rockville Centre St. Patrick’s Day Parade.

Where Ireland is concerned, William Flynn has always been out front as a tireless and undaunted peacemaker. A prominent insurance executive with a realistic grasp of economics, he patiently labored for more than five years with IRA, Ulster militants, Northern Ireland and British delegates to forge the 1998 Good Friday Agreement that halted decades of sectarian slaughter and destruction known as “The Irish Troubles.”

So far the cease fire has held, and both the Irish Republic and Northern Ireland are undergoing a remarkable economic recovery.

Far from the cheering crowds lining the parade routes graced by Ed Wilkinson and Bill Flynn, your humble columnist, Cathedral Prep class of 1942, was Grand Marshal of the 1983 St. Patrick’s Day Parade in O’Neill, Nebraska.

And thereby hangs a tale worthy of a pint or two anywhere on St. Patrick’s Day.

O’Neill, which bills itself as the “Irish Capital of Nebraska,’’ is named for Union Capt. John O’Neill, who fought in the Civil War with the 17th Colored Infantry, a unit of freed slaves.

Born in Ireland, he never gave up the dream of freeing Ireland from British control. When the war ended, he got the madcap idea of invading Canada with Irish veterans of both Union and Confederate armies and then giving her back in exchange for a free Ireland.

Actually, O’Neill and his bold Fenian lads invaded Canada three times, always on or near Queen Victoria’s birthday, and always ending in a fiasco. In 1866, they mustered at Buffalo, crossed the Niagara River and hauled down the Union Jack flying over the customs post at Fort Erie. The gunboat USS Michigan arrived to break up the Queen’s birthday party and scatter the invaders.

To the Prairies

O’Neill tried again in 1870, this time crossing into Canada from Vermont. The lads liberated a hat shop and a liquor store before federal troops led by Gen. George Meade, the victor at Gettysburg, sealed off the border and arrested the ring leaders. Confined to jail in Burlington, Vt., O’Neill hatched the idea of settling Irish immigrants “out on the virgin prairies,’’ away from the crime and corruption of the big cities.

The first settlers arrived in 1875. When the railroad came through five years later, the population jumped from 57 to 1,226. The town eventually was named for O’Neill, who made one more futile foray into Canada across the Minnesota border.

I probably was chosen as Grand Marshal because Mulligan’s Stew, a column I wrote for The Associated Press, appeared regularly in the Omaha World Herald. It was a grand parade, with lots of school bands, Boy and Girl Scouts, Future Farmers, a procession of farm equipment and colorful floats, like one proclaiming O’Neill “The Popcorn Capital of the World.’’

For a time, the Grand Marshal was grandly enthroned in the bucket of a John Deere front loader. The driver suddenly and precariously lifted the bucket in salute when we passed the town hall and St. Patrick’s Church.

I still cherish the Key to the City and the shillelagh given to me by Mayor E.M. Gleeson. I’d like to go back to O’Neill some St. Patrick’s Day to see if that green water tank still proclaims its Irish heritage and if they have added a second traffic light.