The reasons proffered center on the defensive lines of barriers that Ukraine as developed in holding onto the region and the barbarian’s demand that Ukraine surrender the region so he doesn’t have to fight his way across them.

Russia wants the entire region of Donetsk, including the 25% that Ukraine still controls, an unoccupied swath larger than Delaware. A heavily reinforced defensive line, known as the fortress belt, has stopped the Russians from rolling deeper westward, and Ukraine has no plans to surrender the area.

That’s entirely wrong. The Ukraine defense works are, in fact, every bit as formidable to a modern army as the Maginot Line was to then-modern armies. That’s why the Nazi German forces bypassed the line in Nazi Germany’s invasion of France, even violating Belgian neutrality to do so. So it is in eastern/southeastern Ukraine.

Is it a sign of Russian weakness to demand the region as the article’s subheadline has it?

It is the site of a reinforced defensive line, the “fortress belt.” Putin’s demand for it is a sign of weakness.

No. The defensive barriers are neither here nor there. As with that Maginot Line, it would be straightforward enough for the barbarian to bypass those barriers, here, around either or both ends. On the contrary, it’s a sign of Russian recognition of the industrial importance of the Donetsk to Ukraine (recall the deindustrialization of Germany and the packing up and moving of whole factories from western Germany into eastern France at the end of WWI), and it’s a sign of the importance of the mineral and rare earth wealth of the Donetsk both to Ukraine (and to the West) and to Russia.

The sooner the West recognizes that and internalizes it, the sooner the West can set about properly supporting Ukraine in the latter’s war for survival.