Don’t be so sure. The guidance system in the Tomahawk cruise missile was deemed an expensive failure. That was so our enemies had no idea. Decades of superiority because we were successful enough and mature enough to know that loose lips sink ships.
Without knowing “what system” and “what kind of missile” and “what kind of test” we wouldn’t be able to say anything about the whole picture.
If something did come at Hawaii from North Korea, it would have every antimissile missile that we could muster chasing after it. This might have been just one.