Knife Guy:

I’m no expert, but I’ll give it a shot.

If we had had internet forums thousands of years ago, thrust vs. cut arguments would have gone on as interminably as 45 caliber vs. 9 mm arguments do today. Then there would be the smart [censored] who wanted to design a sword that would be equally good at both. It will never happen, the handling characteristics of the two types of sword are incompatible. I do believe that the katana is as successful at combining cut and thrust as any other type of sword I know of. Even the small amount of martial arts training I’ve had included the occasional thrusts in the sword kata.

Obviously the katana is mostly designed for slashing. And specifically for the draw cut. I had a karate teacher years ago, who used to do the trick of putting an apple on the bare belly of one of his students, and then slice it in half—the apple, not the student. No matter what, you need excellent control to pull such a stunt. Sinsei explained that it was safer than it looked as long as he only chopped. The curve of the katana is specifically designed to maximize the result of the draw cut. Had he ever slipped and used a draw cut instead of a straight chop, there would have been guts on the floor.

I’m no expert, but I’ve never seen a katana or wakizashi with a swedge. I think the reason can be found in Japanese history. When Kublai Khan sent an invasion fleet to Japan, the samurai were shocked to find their weapons were ineffective against sturdy Mongol armor. Even worse, Mongol swords and arrows pierced Japanese armor just fine. If it had not been for the kamikaze “divine wind” that sank the Chinese fleet, Japan would have been conquered. Several things happened between that invasion and Kublai’s second attempt. Among them, defensible rock walls were built along every possible beachhead on the Japanese shore. And Japanese weapons and armor were improved. Both were made heavier, the better to pierce the invader’s armor while avoiding the converse. This was true of yari and naganata and war bows. It was true of samurai armor. It was true of swords. Katanas were made heavier, the better to slice or pierce Mongol armor. Many samurai used the larger dai-katana. Or the even larger swords called horse-killers. (Sorry, I can’t remember their Japanese name.) It worked, too. Kublai’s boys had a much harder time of it on their second try. They were still defeated in the end by a second kamikaze. (I do wonder about the Chinese navy. Didn’t the admiral know when typhoon season was?)

My point is, either for the cut or the thrust, the katana was designed to deal with armor. It was a battlefield weapon. Right through the establishment of the Tokugawa Shogunate a samurai could expect to fight against masses of men wearing tough armor. Japanese armor was lighter than European armor of about the same period, true. But it was still tough work to slice and dice a man wearing good armor. Beheading an opponent was expected. Showing the heads of the men he killed in a battle was how a samurai increased his prestige. Cut or thrust, that blade had to work. Piercing armor requires a strong fast thrust that will shock the blade, especially the point. With the extreme differential tempering of the katana, adding a swedge would have been disastrous. It would remove some of the tough flexible steel that was needed to absorb the shock and support the brittle edge. This was as true for the cut as for the thrust. In these circumstances it is better to have a strong tip than a tip that might be more efficient but is necessarily weaker.

It’s true that things were more peaceful through the Edo period. With the civil wars over, battles were rare. But the Japanese honored tradition. The “soul of the samurai” kept its battlefield tip until the Meiji restoration outlawed the wearing of the two swords.