Belgium has ruled that some aspects of Facebook data collection are illegal, and ordered Facebook to delete the data or face a large fine.

While this is firm compared with the usual levels of regulation of companies nowadays, it is inadequate in recompense because it assumes that deleting the data will entirely undo the wrong to the users. There are two reasons that is not so:

• Facebook has already had a chance to manipulate and mistreat users by means of that data.
• The US government may have collected some of that data, using PAT RIOT Act blanket surveillance powers. If Facebook deletes that data now, that won't make the US delete it.