> As these were not logistical flights, they were not covered by the bilateral treaty governing U.S. military bases in Italy which allow for logistical and technical use; that led Defense Minister Guido Crosetto to deny the planes the use of the Sigonella base since permission in this case would need approval from the Italian parliament.

And:

> their flight plan was not communicated in advance to the Italian air force general staff, nor had the American aircraft received authorization to land,

Sounds like they might have gotten authorization if they had just told them in advance.

What is a logistical flight?