How do you raise the flag on the mast of a ship that has no mast?

It wasn’t the biggest problem the Michael Monsoor had faced in years of planning, construction and setbacks. But the ultra-powerful destroyer required a flag-raising for its commissioning Saturday at Naval Air Station North Island in Coronado.

So the Navy constructed a temporary “mast” atop the ship. Dignitaries spoke before an estimated 5,000 people, the American flag was raised, and its crew called on board.

And that’s how the Monsoor officially entered service as the second of three high-tech — and expensive — Zumwalt-class guided missile destroyers.

The Monsoor’s unconventional blocky, low-profile outline — which made the mast improvisation necessary — has inspired jokes comparing it to a “Transformer.”

Civil War buffs might notice that the Monsoor’s silhouette hugging the water strongly resembles that of the ship Virginia, the terrifying Confederate ironclad that in 1862 opposed the Union’s Monitor in the Battle of Hampton Roads.

Like the ironclads, the Monsoor represents a new kind of vessel, which has endured snafus common with development of new technology. The $4.6-billion ship has also endured delays, including the replacement of its engine.

But while the ironclads were slow, clumsy and barely seaworthy, the Zumwalt class destroyers are sleek, speedy and designed to hit targets many miles away.

The class is named after Elmo R. Zumwalt Jr., chief of naval operations from 1970 to 1974. The first ship was named after Zumwalt himself. The third and last is named for President Lyndon B. Johnson.

The naming of this particular ship for the late Navy SEAL Monsoor was apt, said speakers led by Rep. Scott Peters (D-San Diego). Zumwalt was dedicated to the entire Navy, making a point of eradicating any racial or sectarian differences among sailors. Monsoor made the ultimate sacrifice to save his fellows in SEAL Team 3.

When an enemy grenade was thrown into their position in the battle for Ramadi, Iraq, in 2006, Monsoor leaped onto it, taking the blast to save the others.

In so doing, Monsoor “lived his faith,” Peters said. “He was a devoted Catholic who attended Mass daily, even in the theater [of war].”

Monsoor, Peters noted, was named after St. Michael the Archangel, the patron saint of warriors. That history is symbolized in the ship’s crest, which bears a winged arm wielding a sword.

And it was on the Feast Day of St. Michael, Sept. 29, when Monsoor threw himself on that grenade.

Monsoor’s mother, Sally Monsoor, is the ship’s sponsor. She christened it in 2016 in Bath, Maine, where it was built.

On Saturday, she gave the commissioning order, kept short for the audience’s comfort, she said, because of the hot sun.

“This is the fun part,” she said. “Officers and crew of the USS Michael Monsoor, man our ship and bring her to life.”

The audience roared.