We have nearly all of the extinction level asteroids detected. It is really unlikely that one on collision course would be detected. There could be dangerous comet which appear suddenly but those are even less likely. The other problem is that they are big enough that might be hard to divert.
The test one is small enough that it wouldn’t do that much damage. Worth the expense to send spacecraft to divert something that could destroy a city. Not worth wrecking civilization to protect a city. Most of asteroids we haven’t detected are the smaller size.
Finally, Orion isn’t necessary. Nukes are small, you could send up a bunch in Starship. We could also come up with better propulsion, like nuclear rocket, that would be useful. Orion would be stupid expensive for very unlikely contingency.
You are probably correct in about ... six months when Starship officially hits orbit.
The only real thing that Orion has going for it is that it is brutally effective. If we need something to launch fast, it might not be that much on civilization level effort to get a big honker going.
The test one is small enough that it wouldn’t do that much damage. Worth the expense to send spacecraft to divert something that could destroy a city. Not worth wrecking civilization to protect a city. Most of asteroids we haven’t detected are the smaller size.
Finally, Orion isn’t necessary. Nukes are small, you could send up a bunch in Starship. We could also come up with better propulsion, like nuclear rocket, that would be useful. Orion would be stupid expensive for very unlikely contingency.