The Hanseatic League as a maritime deterrent

How serious was the Hanseatic League as a naval war machine?

The Hanseatic League was capable when war became necessary, but preferred trade backed by the collective deterrent of many wealthy cities.

The Hanseatic League preferred trade to war, but that preference did not make it militarily irrelevant. Its network of cities around the Baltic and North Sea created collective safety for merchants. Individual trading cities faced kings and nobles who could profit from coercion or conflict. Acting together gave them a deterrent much larger than any single port could sustain. For that deterrent to work, the league still needed a credible ability to fight when challenged.