cthia wrote:I couldn't understand why the Forts never engaged. Tourville would have been kept off balance by the planetary Forts if there had been any. The Forts have a paltry 50g of acceleration which is much too slow for a tactical redeployment, but at an ETA of 3 days, that is plenty of time for a strategic redeployment.
In 3 days, the battle had been over for two and a half.
That thread brought up concerns that the Forts would invite return fire that could impact with the planet, if they engage. But what are planetary forts for if not to engage the enemy? Are they simply there to bluff? Under what conditions would planetary forts engage the enemy?
They are the last line of defence. Mind you, I don't completely agree with not firing at all. The fall out from strikes on defensive installations is on the shoulders of whoever placed the installations there in the first place (assuming the use of force by the attacker wasn't disproportionate). Therefore, if it's ok for forts to be in orbit, then it's ok for the forts to be attacked.
The question is the timing. Would the attacker (Tourville in this case) take the time to set up proper shots to take the forts out? Or would he hope to force them to surrender once he had control of the outer system?
Remember the planning that Theisman told Pritchart: the Havenites had a fleet train waiting in hyper with at least one full reload. If Tourville and Chin had been successful, they could resupply all their missiles and tow a significant number of pods to fire at the forts, hoping to eventually overwhelm them with numbers ("quantity is a quality of its own"). They could hold the MBS for weeks, which is the time it would take for reinforcements to arrive from New Berlin, Grayson or Eighth Fleet to return from wherever it had gone to; but they could hold for a couple of days.
This would be time for the Junction forts to make a move, indeed, but they are sitting ducks while moving. They are too slow, so the SDs attacking them can perform hit-and-run tactics. I don't know if there's enough time to do that before they arrive at the planet, but then the Junction forts at the planet are no better than the planetary forts would be either. If the latter were taken into account in the planning, then adding more forts wouldn't make that much of a difference.
Oyster Bay resulted in debris that impacted the planet, but the RMN never saw that attack coming. During the BoM, wouldn't there have been plenty of time to preposition tugs?
Yes.
Also, why aren't attackers held responsible for impacts with the planet by missiles which end up far beyond the targets that they engaged? Are missiles not programmed to self-destruct beyond a certain range? IOW, I thought the planetary forts simply had to ensure that they took up position far enough from the planet.
Because the positioning of defences is the defender's job and responsibility. If you place a defence installation in the middle of a civilian population and that gets attacked, the civilian losses are the defender's responsibilities. In other words: you can't use civilians as shields.
So you're right, one simple solution might be to move the forts sufficiently away from the planet that the most confused missiles wouldn't mistake fort for planet.
There was some discussion of what happens to the debris of a missile that did decide it couldn't attack the fort and therefore self-destructed. It's still moving at 0.81c relative to the fort and planet. If the fort is half a million km from the planet (beyond the Moon's orbit for us) and the missile self-destructed within 25,000 km of that, it's going to be at about 500,000 km from the planet, or 2.05 seconds from possible impact. The planet is not THAT big of a target in astronomical terms, but once the missile self-destructs, it can't manoeuvre.
And missiles that were taken out by PDLC can't manoeuvre either.