Vienna, Nomad-Proof?

It is well known that Vienna was the last bastion of the "West" against the Ottoman Empire, and that a crescent-shaped pastry was developed there to celebrate the repulsion of the Turk.  That pastry, brought to Paris by the Austrian Marie Antoinette, became the croissant, propping up the bottom lines of cafes across the globe.

Recent reading reminded me of a not forgotten, but perhaps less celebrated fact, that Vienna also represented the western limit of the original conquests of the Mongols, who had easily taken control of Hungary under Batu Khan with a mixed Mongol and Tatar army.  But the death of Ögedei Khan [Өгэдэй хаан] led the Mongols to suddenly pack up and return home in anticipation of a fight for succession to the throne.  And so Vienna was never invaded.

Does that make it immune to any future nomadic invasions?  More likely, this kind of luck comes with an expiration date.