"Be with him at every mail call" was a motto used by the U.S. government to encourage frequent letter writing to military men overseas. The U.S. military considered letters a powerful morale booster. Letter writers were told to be positive and "cheery," to provide details of home life but never to include information that might be useful to the enemy if the letters were captured. Magazines featured articles on the "do's and don'ts" of letter writing. Wives, mothers, sweethearts, grandmothers, sisters, aunts, nieces, and neighbors all wrote. For many it was a daily ritual. It usually took a letter six weeks by boat to reach the intended soldier.

Letters took up so much cargo space that the government developed V-mail. V-mail letters were written on special 8 ½-by-11-inch forms that could be purchased at local stores or the post office. Once the letter was written, the form was then returned to the post office and sent to the military where it was photographed. The film was flown to a mail center near the recipient's position. There the film was developed, and the V-mail was delivered in the form of a 4-by-5 ½-inch photograph.

Approximately seventeen hundred V-mail letters could fit in a cigarette packet. V-mails reached soldiers by air in twelve days or less. Over a billion V-mails were sent during the war. The V-mail process was the beginning of microfilming.