While Don was in Sigalla, Ken had been working as a horse from Everlight to Agoria. In Everlight, he helped Vivian with forming a special unit of soldiers called police. In his time, the military dealt with the things that mostly have anything to do with the outsiders while the police unit took care of the internal things such as catching murderers and thieves or anything like that.
In Agoria, he was constructing steamboats. Compared to the airships, submarines, and the undefeatable navel force they had in his time, the steamboats were primitive technology to him.
At the current moment, they had neither the resources nor the technologies to build an airship nor submarine. But for the next couple of years, the steam boats could dominate this current world.