The impressive performance of the German 88mm FlaK series forced the US Army to consider adopting a similar weapon. The 90mm M1 cannon was designed in response; it is a dual-purpose artillery piece, capable of engaging both tanks and aircraft. The M1 line of 90mm guns has a number of variants, though the most common is the M2 with improved direct-fire capabilities and the M3 tank gun. The latter became the standard cannon of America's early MBTs. An effective weapon even in the modern day.

90mm Gun M1
Fire Support Weapon
Abilities
Common Attributes - National
Keep 'Em Firing! - American Artillery (WW2)
American artillery in World War II was renowned across the world for its seemingly endless supply of shells, and as a result, the over-the-clock support it could give G.I.s fighting across Europe and the Pacific. Any infantry company could bring about a hellish gun barrage with a quick telephone call.
EFFECT:
Once per Engagement, this cannon may perform Indirect Fire (2 AP) 3 times against any single target, instantaneously reloading, in a single Turn.
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