Hence "even if degraded" / "reconstitute faster"... relative post war reconstituting shipbuilding including infra is downstream of capable workforce. During war surface industry can't be protected (likely including CONUS). Post war, shipyards / industrial supply chains can be rebuild faster than it takes to train the workforce to man them. Shipyards also inherently fortified structures, the labour intensive part - earthworks, concrete - are hard to crack, at scale. Jiangnan (launched more GTs than whole of US post WW2 production), is like ~5x the size of all WW2 JP shipyards combined, it's not something US can substantively blowup. PRC a whole different scale of adversary vs what US historically calibrated to fight conventionally. VS relatively weaker USSR, US plan was basically to nuke their industry, nuke the fulda gap - conventional forces not scaled to cripple peer powers in their backyard. Regardless domestic shipbuilding isn't about ongoing sustaining war efforts anymore, it's about recovering from one, especially for maritime powers who knows their entire surface fleet could be wiped.