How did sea mines change the war?

Sea mines significantly altered naval warfare by creating barriers that restricted the movement of enemy ships, making it difficult for them to navigate key waterways. They were used effectively in both World Wars to protect Coastlines and strategic ports, leading to a shift in naval tactics and the development of countermeasures, such as mine-sweeping operations. The threat of mines forced navies to reconsider their strategies, emphasizing the importance of intelligence and technology in safe maritime operations. Ultimately, sea mines contributed to the overall complexity and lethality of naval engagements.