Supercavitation-Expialidocious!

Torpedo Troopers:

I wouldn't fancy being the test-pilot for this project - a massive troop-carrying torpedo designed to churn through the water at more than 100 knots (115 mph).

To reach such speeds the vehicle would make use of supercavitation, an effect that occurs at high speeds underwater when a bubble of gas is generated around a suitably-shaped object. This reduces drag dramatically and allows the object to hurtle through the water at blistering speeds. The effect is already exploited by some weapons like Russia's VA-111 Shkval torpedo, which produces gas at its nose to force supercavitation to occur.

This would be both exhilarating and terrifying to ride. It might also be much safer on the net for landing troops than surface transports.

Another less hi-tech military innovation just came out -- uniforms with built-in tourniquets. Most preventable combat deaths occur due to blood loss from leg and arm wounds. While the thought of needing to use a tourniquet sounds awful, the thought of needing one and not having it is far worse.