LIMITED TIME ONLY! RECEIVE A FREE COPY OF MARTHA MACCALLUM'S NEW BOOK WITH ANY YEARLY FOX NATION PLAN

Seventy-five years ago this week, approximately 70,000 U.S. Marines invaded a tiny, volcanic island more than 600 miles south of Japan. The ensuing battle became one of the bloodiest of World War II.

Among the American troops landing on the black sand beaches of Iwo Jima was Harry Gray from Arlington, Mass.

He was 18 years old when he boarded the USS Rochambeau bound for the island and, like nearly 7,000 fellow Marines, he would never again return home.

Gray was the son of Harry Sr. and Anne Gray, and cousin to Elizabeth Jane Bowes, who is Fox News anchor Martha MacCallum's mother.

In her new book "Unknown Valor: A Story of Family, Courage, and Sacrifice from Pearl Harbor to Iwo Jima," MacCallum reexamines America's war against Japan, illustrated through the letter and recollections of those who fought, and some who died, in that struggle.

"This is a story of closure, of [Martha] meeting some of the men that fought beside [Harry Gray] and finding out what happened," said Fox Nation's Kacie McDonnell on "Fox and Friends" on Thursday, describing the book and an upcoming Fox News and Fox Nation special.

On Sunday, Feb. 23 at 10 p.m, Fox News Channel will broadcast the special also called "Unknown Valor: A Story of Family, Courage & Sacrifice," and the directors' cut of the program will be available on Fox Nation immediately afterward.

A bonus edition of MacCallum's special on Fox Nation, called "Minutes to Hiroshima," details the development, construction and deployment of the weapon that would bring an end to the war in the Pacific.

"It was on Tinian, a small island, 2,500 miles south of Tokyo, where American construction crews created a staging area to assemble the atomic bombs," narrates MacCallum in the Fox Nation special.

Today all that remains of this top-secret mission is the concrete slab of a building, loading pits once used to hoist the weapons into the bombers, and the runway where the Enola Gay took off bound for Hiroshima.

"With all the pieces in place, the bomb that would change the face of warfare was loaded onto a transport trailer and given one final look," says MacCallum in the special. "It was then shrouded in a tarp and amid a backdrop of sandy beaches escorted to the Northfield airbase."

"The bomb was secured and the equipment checked yet again," she concludes. "Finally it was ready for Japan, where the $2 billion Manhattan Project would come to an explosive end."

To watch all of "Minutes to Hiroshima" go to Fox Nation and sign up today.

LIMITED TIME ONLY! RECEIVE A FREE COPY OF MARTHA MACCALLUM'S NEW BOOK WITH ANY YEARLY FOX NATION PLAN

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