Rolling barrages and tanks answered the killing zone

Armies began seeking ways to overcome the changed battlefield in the opening months of the war. Artillery could suppress defenders even when it could not reliably destroy their positions. Rolling barrages moved fire forward so infantry could close before machine-gun crews returned to their weapons. Tanks provided protected, moving fire support and absorbed fire that would otherwise strike the infantry following them. The Mark V example emphasizes direct-fire suppression of machine-gun positions as part of opening a route through the defences.