The SOP of the chase boats is to get in front of the whalers and drop nets and ropes to foul their props. The Ady Gil was the perfect boat to do this, stealthy and fast to get in front of them, drop the fouling and get out.
The Japanese know this, and their only choice is hard maneuver to avoid or stop their props and hope it doesn’t catch. As far as the water cannons all I can say is that should be about the least of their worries. I don’t know if they were trying to foul the props, but doing that in international waters, especially in that part of the world to a ship is a criminal act deserving a harsher response than acoustic weapons and fire hoses.
the Japanese have every right to hunt whales according to the IWC. If a ship prevents that legal persuit it is a PIRATE SHIP and should be sunk and if necessary with all hands.
Change the laws if you want them to stop whaling.