After the opening months of movement and maneuver warfare, WWI on the Western Front stagnated into gridlock as exhausted armies dug in where they stood. By the end of 1914, millions of soldiers faced enemies across no-man’s land while hunkered in trenches that stretched for hundreds of miles from the Swiss border to the English Channel. Direct attacks on entrenched opponents typically resulted in advances of a few hundred yards, or a few miles at most, and produced little other than mutual attrition, with attackers suffering significantly higher casualties commensurate with their greater exposure in the open to concentrated machine gun and artillery fire as they traversed no-man’s land.
Operation Hush in 1917 was a British plan to take advantage of Allied naval supremacy, cemented by the Royal Navy’s strategic victory in the Battle of Jutland the previous year. It aimed to outflank the Germans with an amphibious landing on the Belgian coast, behind the German trenches’ northern terminal on the English Channel. The horrors of trench warfare in that stretch near the coast were exacerbated by marshy ground that reduced the area to a sea of mud.
The idea was to first attack the German trenches with a normal ground assault across the area’s flooded no-man’s land. Once a sufficient advance had been made, such that a breakthrough out of the muddy region and into the dry land beyond was attainable, the British would land a force on the coast behind the enemy trenches, which would then wheel right and attack the rear of the Germans resisting the initial attack from Ypres. Pinched front and rear, the Germans defenses would crumble, and the British would advance over them to link with the amphibious force on dry land. With the muddy region which had made advance so difficult now behind them, and open dry land ahead, the British would have better prospects for future operations.
Unfortunately, the Germans grew suspicious and launched a spoiling attack in July, 1917, that pushed the British back. When the main British attack finally came, the Third Battle of Ypres in October of that year, it had to make an even greater advance than the planners of Operation Hush had envisioned. First, it had to recapture the ground taken by the Germans in July. Then, continue until close enough to the beaches where the amphibious force would land. The British failed to advance far enough to come within striking distance of a linkup with an amphibious force-landed behind German lines, so Operation Hush was cancelled.