Early snorkels would make First World War U-boats harder to counter

What if Imperial German submarines had snorkels by late 1914?

Germany would come closer to success because U-boats could remain submerged more often and become less vulnerable to patrols and air attack; design changes would still take time.

Early submarines were torpedo boats that could dive only intermittently, making their surface exposure a major weakness. A snorkel would not instantly create a Type XXI, but it could encourage earlier development toward larger boats designed for better underwater performance. Remaining submerged while running diesels would reduce exposure to patrol craft and aircraft during a campaign in which U-boats already pressed Britain hard. Limited torpedo capacity would keep deck guns relevant at first, so the design shift would more likely accelerate larger UB III-type boats than immediately remove every surface feature.