The Long Blue Line: “Plan One, Acknowledge” and the Coast Guard’s military baptism of fire

By Written by William H. Thiesen, Ph.D. Coast Guard Atlantic Area Historian

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“Were such a reminder necessary, I feel sure that the splendid record of its forbear, the Revenue-Cutter Service, in all the previous wars in which this country has engaged, would serve as an incentive to the officers and men of the present Coast Guard to maintain unsullied its past reputation for heroic deeds in battling the Nation’s enemies.”
Treasury Secretary William McAdoo

Official photograph of the Secretary of Treasury, William G. McAdoo, who served during the 1917 transfer of the Coast Guard to the U.S. Navy. Photo courtesy of the Library of Congress.
Official photograph of the Secretary of Treasury, William G. McAdoo, who served during the 1917 transfer of the Coast Guard to the U.S. Navy. Photo courtesy of the Library of Congress.

McAdoo wrote the words above to U.S. Coast Guard Commandant Ellsworth Bertholf on Friday, April 6, 1917, the day Congress declared war on Germany. That same day, the U.S. Navy’s communications center in Arlington, Virginia, transmitted the code words “Plan One, Acknowledge” to Coast Guard cutters, units and bases throughout the United States. This coded message initiated the service’s transfer from the Treasury Department to the Navy placing the service on a wartime footing.

Prior to World War I, President William Taft’s administration had nearly disestablished the U.S. Revenue Cutter service, the Coast Guard’s predecessor service, as a cost-cutting measure. Taft proposed to dismantle the service and distribute its assets and missions between the Navy and other federal agencies. But contemporary events convinced American political leaders to scrap this plan. In April 1912, the Royal Mail Ship Titanic struck an iceberg and sank in the North Atlantic. The accidental sinking of this “unsinkable” passenger liner and the consequent loss of life shocked the public on both sides of the Atlantic, initiating the 1913 Safety of Life at Sea Convention in England and the establishment of the International Ice Patrol. Originally supported by the Navy, this patrol tracked icebergs and reported their location to ships in the North Atlantic. Soon after the establishment of the International Ice Patrol, the Navy could no longer spare ships for patrols, so the Revenue Cutter Service assumed the duty.

Ellsworth P. Bertholf, first commandant of the modern Coast Guard. Coast Guard Collection.
Ellsworth P. Bertholf, first commandant of the modern Coast Guard. Coast Guard Collection.

In 1914, another service-related event took place when war erupted in Europe. As the conflict spread to other parts of the globe, President Woodrow Wilson saw the benefit of retaining the Revenue Cutter Service as an armed sea service. And, when combined with the U.S. Life-Saving Service, the assets and personnel of the two agencies would prove effective in guarding the nation’s shores both by land and at sea. On Jan. 28, 1915, Wilson signed the “Act to Create the Coast Guard,” combining the Life-Saving Service and the Revenue Cutter Service into one agency. The act went into effect on January 30, establishing the United States Coast Guard as a military agency that would serve as a branch of the Navy during conflicts.

After the Coast Guard’s formation, it became clear that the service would play a vital role in future U.S. naval operations. From 1915 through early 1917, the Navy and Coast Guard collaborated to develop mobilization plans transferring the service from the Treasury Department to the Navy in time of war. In early 1915, Bertholf began meeting with his Navy counterparts and developed a 20-page report that evolved into the confidential document “Mobilization of the Coast Guard when Required to Operate as a Part of the Navy.” This document included the Coast Guard’s “Mobilization Plan No. 2” for combining the two services in peacetime and “Mobilization Plan No. 1” for combining the two services when war was declared.

Soon after the Navy transmitted the April 6 “Plan One, Acknowledge” message, the Coast Guard answered the call. For example, at 6:00 pm, San Francisco-based cutter McCulloch received telephone instructions from its division commander to put into effect Mobilization Plan Number One. By 7:25 pm, the cutter received a similar “ALCUT (all cutters)” message from Coast Guard Headquarters. In response, the McCulloch transmitted to the local Navy commander a coded radiogram reading “Commanding Officer, U.S.S. Oregon. Mobilization orders received. Report McCulloch for duty under your command.” In addition to McCulloch, nearly 50 cutters and 280 shore installations came under Navy control.

Coast Guard cutter McCulloch, which received the coded message “Plan One, Acknowledge” on April 6, 1917, as did all Coast Guard units, stations and bases. Courtesy of National Oceanic and Atmospheric Administration.
Coast Guard cutter McCulloch, which received the coded message “Plan One, Acknowledge” on April 6, 1917, as did all Coast Guard units, stations and bases. Courtesy of National Oceanic and Atmospheric Administration.

World War I proved the first true test of the Coast Guard’s military capability. During the conflict, the service performed its traditional missions of search and rescue, maritime interdiction, law enforcement and humanitarian response. Meanwhile, the service undertook new missions of shore patrol, port securitymarine safety, and convoy escort duty while playing a vital role in naval aviation, troop transport operations and overseas naval missions. By war’s end, these assignments had become a permanent part of the Coast Guard’s defense readiness mission.

The war cemented the service’s role as a military agency. Nearly 9,000 Coast Guard men and women would participate in the war. This number included over 200 Coast Guard officers, many of whom served as warship commanders, troop ship captains, training camp commandants and naval air station commanders. In all, Coast Guard heroes received two Distinguished Service Medals, eight Gold Lifesaving Medals, almost a dozen foreign honors and nearly 50 Navy Cross Medals, dozens more than were awarded to Coast Guardsmen in World War II.

Coast Guard boat station crew at Quonocontaug, R.I., dressed in their World War I uniforms. Coast Guard Collection
Coast Guard boat station crew at Quonocontaug, R.I., dressed in their World War I uniforms. Coast Guard Collection

World War I also served as a baptism of fire for the Coast Guard. During the war’s nearly 19 months, the service would lose almost 200 men and five ships. These ships included two combat losses. On Aug. 6, 1918, U-140 sank the Diamond Shoals Lightship after her crew transmitted to shore the location of the marauding enemy submarine, but no lives were lost. However, on Sept. 26, 1918, after escorting a convoy from Gibraltar to the U.K., Cutter Tampa was torpedoed by UB-91. The cutter quickly sank killing all 131 persons on board, including four U.S. Navy men, 16 Royal Navy personnel and 111 Coast Guard officers and men. It proved America’s greatest naval loss of life from combat.

In the years following the war, the Coast Guard would develop into a robust military agency. Prohibition saw the service become the lead agency fighting the “Rum War,” increasing the Coast Guard’s size and technological sophistication. In this war against liquor smugglers, the service operated 31 of the Navy’s four-stack destroyers. It was the first time in history that Coast Guard crews had manned Navy warships. Prohibition also saw the first congressional funding for Coast Guard aviation to help fight the rumrunners; and, the establishment of the Coast Guard Intelligence Office, a leading federal intelligence branch that would also decipher enemy codes in World War II. And, 1932 saw the completion of the modern Coast Guard Academy, which produced many of the service’s combat leaders of WWII.

World War I Coast Guard and Navy officers pose together for a photograph. Coast Guard Collection.
World War I Coast Guard and Navy officers pose together for a photograph. Coast Guard Collection.

World War I would prove the first true test of the modern Coast Guard’s military capability. This baptism of fire also cemented the service’s place among American military agencies and prepared it for the challenges it would face in World War II.


Image Gallery

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CGD 24 Wainwright Unknown port; photo taken from quarterdeck of unnamed USCG cutter. Boston? Photo...
USCG patrol boats during Prohibition
"Coast Guard Destroyer Downes (From a Painting by the Destroyer Force Bugle Staff Artist, Marius...
"Ensign Roland making end run, Coast Guard-Marine game, Washington, D.C., 1929." Scanned from...
"1929 - Coast Guard Football Team - 1929. Back Row: -Lieut. Baker, Coast and Manager; Wineke,...
A photo of Coast Guard Destroyer CONYNGHAM on patrol during Prohibition.
Coast Guard Destroyer's baseball team (no date).
Hand-written caption on reverse of photo reads: "Officers and crew of CGC Beale (Navy destroyer...
Hand-written caption on reverse of photo reads: "R R Waesche Sr., CGC Snohomish, Port Angeles, or...
"BEALE (CG-9) (Of the old U.S. Coast Guard Destroyer Force - 1924-1930) An early 20th century...
"Engineroom Force of the Coast Guard Cutter PONTCHARTRAIN. 3-5-29 (1)." CCG Scrapbook (CG...
Copy photo found in the CG Historian's Office Special Collections Archive in the "Uniforms" folder....

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