Well, the theft of paintings from De Kunsthal you are referring to is incomparable to the situation at Noordeinde. The security situation at De Kunsthal was flawed already and they had an easy time getting in there. Noordeinde is already well secured, and the jewels are stored there. De Kunsthal is a private entity, Noordeinde a government building. If the Dutch government, with the royal and diplomatic security service, can't secure the palace, who can?? The value of the art in Rijksmuseum by far outshines the jewellery collection of the Dutch Royal Family, for example.