It's the treasures they go for first.
If you are a tiny town without treasures, as with Havre de Grace on the Eastern Shore of Maryland during the Brit blockade of the Chesapeake in the War of 1812 they'll take your baby's cradle and burn your house for good measure.
In Detroit that means the art, which booty is already being quarreled over.
Chicago, it's seizure of the public schools that are the opening battery. In New Orleans it was the schools, and the hospitals, just like here in NYC, though here we've added the public library system to the list. Real estate is one reason. Teachers and nurses, their unions, i.e. their voting affiliations another. Then there are the pensions, which, as in Detroit, are found often already looted. In other words, anything that is part of public, community service, pleasure and support is under relentless attack in the war to transfer all such assets everywhere to the private, i.e. corporate-real estate plutocratic oligarchy.