The US has European allies who are quite savy in coastal mine warfare and who provide most green water capability of NATO (NATO is not dead). Unlike the Europeans, the US Navy thinks only very big ships are a very save place to be (that won't go down with loss of life and investments). So minesweeping can be done only by aerial assets, helicopters are their first choice and USV are the next thing to come because these are cool new tech. Other than that, the US Navy wants to have minesweeping capability internal to all their ships rather than small "indefensible" platforms specialized for that task.
This US view does have merits, but doesn't come cheap and the monetary expenditure is at a level of much reduced returns of system performance because of the big size bias in all US military aspects.
A competitor could choose less complex platforms at a higher level of returns per expenditure and thus achieve capabilities close to the US naval integrated systems capability at a lower price (Japan tried that in WWII and failed, so take them as an example how this can go wrong).
---------- Post added at 09:41 PM ---------- Previous post was at 08:57 PM ----------
Where is Kurt He loves mine/Here is a good article on Chinese mine
I read it. Mines are "nice", but the future will likely be increasingly less systemic approaches of automated data-processing machines for unmanned access denial, equals the old concept of mines and improvised explosive devices that will go more and more towards improvised unsystemic approaches because of our increased capability to recognize systems (enhanced by AI support).
Supercavitating torpedoes are not yet the best weapon to use from a ship or sub, but just imagine a container of these connected to a complex sensor array with a sophisticated program for interpretation and decisions to act, or even the "deep sea forces" Chinese naval futurists envision. These would be some guys in a bathyscape with fibreoptic wires (fast underwater communication and hard to detect) to run data processing and weapon activation in a modern "minefield". The great advantange of this approach is that you can use anti-helicopter subsurface-to-air missiles against helicopters (that do most US minesweeping and submarine hunting) and supercavitating torpedoes (that are hard to defend against, but have a very loud path and limited range). The bathyscape, old submarine or cheap conventional submarine with fibreoptic connections to external weapon pods and sensor arrays, including active sensors, far enough away from the manned platform, will provide the main minefield threat to military equipment and thus defence for a simple old minefield against sweeps. The old mines will have some upgrades for multi-array sensors and some mobility that both are meant to block run-of-mill civilian shipping with unmanned cheap assets and decrease deployment payload and production costs for the same blocking effect.
The old torpedo going at slow speed for miles into an enemy harbour is one nightmare that reappears in military "fiction", but would in reality have little value, because the closer a naval mishap is to shore and harbour, the easier it can be resolved (Pearl Harbour repair), although it will be quite annoying until it's solved.
The problem with a modern minefield, as described above, is that it needs only a fraction of the payload of minefields of old and very little specialized equipment that is not already in storage for other naval assets, such as submarines, ships and coastal defense, including all the outdated weaponry still in store. The blurred line between mines and munitions means that it will be increasingly difficult to reliably discern mining capabilities from other combat capabilities, expect for the lack of detectable platforms of much value to destroy.
I fully agree that the DF-21 noise for example clouds the vision of many that for a fraction of the cost in "mines" and connected sensors, the same could already be carried out with state of the art technology and that China is likely very capable of doing that (they have the longest tradition in this field and it's one of the few of an unbroken tradition).
But I'd like to ask the question about Chinese mine countermeasure capabilities. In a way emphasizing DF-21 and mine warfare, China's military is depicted as intent on aggressive acts of invasion against a tiny island and not on building some kind of capability to defend multiple interests.