As a matter of perspective, these two battles shouldn’t even be in the same century. The British attack on the German positions in front of Cambrai in norther France were a part of a conflict that Tarawa could not seriously have been a part of, but the slaughter-fest of Tarawa was easily a throwback to the butchery of the Western Front of WWI.
By late 1917 the Allied planners were not only running out of men they were running out of generals willing to use their soldiers bodies as battering rams against each other. 1917 was a weak mirror of 1916’s horrific bloodletting on all fronts from Flanders to the Caucasus. The French Army was on the verge of collapse, the British relying on Canadians and Australians to shore up their staggering troops, and the Americans were unwilling to do what they were supposed to do, which was to turn over their milk-and-beef-fed manpower to the French and British to shore up their bleeding divisions.
So the British turned to Winston Churchill’s “land battleships” that we now know as “tanks.” They had nearly four hundred of the huge mechanical contraptions on hand, and thought that with creeping barrages, infiltrating infantry, close air-ground coordination and some good weather they might achieve a breakthrough that could seize the German supply hub at Cambrai, cutting off supply to the Hindenburg Line and displacing the whole of the German force in France. Although this sounds a great deal like what the Germans would do six months later in the “Michael” offensive and beyond, the British had taken the same lessons from the success of the Huitier tactics first seen in Russia that the Germans who developed them had.
A generation later, the Americans were trying to decide the best way to grapple with the Japanese in the Pacific. With New Guinea in hand, the Solomons more secure than they were, and the Japanese fleet unbalanced, the planners looked at the next step towards the prewar plan to blockade Japan prior to invasion. They needed the Marshall Islands as bases, and from the Solomons and the Allied bases in New Zealand and French Polynesia, that meant they needed the Gilbert Islands. The largest island in that chain was Betio, a part of the Tarawa atoll.
The Americans had spent much of the period between Versailles and Pearl Harbor thinking about how to cross a quarter of the world to bring Japan under its guns. The US Marines were the US Navy’s base-grabbers, and the Marines had been built from the fire team level up to secure the bases needed to do that. But like the large numbers of tanks at Cambrai, they had very little live experience at capturing hot beaches. They had been blooded in the Solomons (where the landing was essentially unopposed) and at Makin (a raid), but their long training and many beach landings had not prepared them for an opposed landing. They knew that the Gallipoli campaign was, to put it mildly, a negative example of what to do. But, tactically, how this would work was still a theory.
Cambrai kicked off on 20 November 1917 with the British Third Army under Julian Byng barraging the German Second and Third Armies under Georg von der Marwitz in front of Cambrai, followed by a fraction (sources differ, but probably more than 400) of the tanks that made it to the front and their accompanying infantry. Though the Germans were ready and had some antitank weapons the sheer number was a problem, even if the early machines were more likely to simply break down than be knocked out by enemy action. The result was an unexpectedly spectacular British success in some places, unexpected failure in others.
At Tarawa, success was a matter of staying alive. By the time the Marines stormed ashore on 20 November 1943 the Americas had pounded the two mile by 800 yard coral rock with more ordnance in three days than the Americans used in their civil war. As the landing craft carrying Julian Smith’s 2nd Marine Division approached the beaches they grounded, often as not, on coral reefs that hadn’t been accounted for in pre-battle planning. No one had expected that around that blasted coral rock, oceanographers would first discover the maximum neep tide that would only occur about twice a year, and not everywhere at the same time. But the landing craft grounded on the reefs that were supposed to be underwater a hundred yards or so from the beach, the ramps would drop, and the Marines would step out into the water often over their heads, and the lucky ones would merely drown. Many of the rest would be shredded by the Japanese of Keiji Shibazaki’s garrison’s automatic weapons and artillery, which were quite unaffected by the American bombardment. By dark on the first day the Marines were barely ashore, their casualties in some companies was more than 50%, and the Japanese just kept fighting.
Cambrai turned into a version of what had already happened over and again on the Western Front: attack, counter-attack, bombardment and repeat. This went on until 7 December, and the territorial gains were minuscule compared to the human cost. Both sides used the new infiltration tactics, but in the end the artillery dominated, as did exhaustion and a weariness of killing. Very little changed for another eighty thousand casualties and a quarter of the tanks in the world.
On Tarawa, the slaughtering went on for three days. The first use of what what would be called “corkscrew and blowtorch” tactics were used against Japanese strongpoints (essentially pinning the defenders down with automatic weapons fire so that flamethrowers could get close enough to be effective). The Marines suffered some three thousand casualties with about half killed out of a 16,000 man division. Of somewhat more than 4,600 Japanese defenders, all but 150 or so were killed.
Cambrai pointed the way to eventual success of armored thrusts and coordinated air/ground tactics, together with quick and intense artillery barrages that the Germans would use in 1918, and again in 1939. Tarawa would point the way to Japanese destruction by isolation because death was their only option as long as they kept faith with the leadership in Tokyo. It would also show the Americans that hot beaches would need somewhat more than raw courage to overcome.