In the South East, they bring you sweetened (usually far too sweetened for my tastes) iced tea. This is amazingly universal.
I live in NC and have been probing the border for years.
For “nicer” restaurants, the universal sweet tea boundary seems to be precisely at the NC/VA border.
Middle East, tea ranges from Moroccan tea to the west to Chai in the east. If you ask for just tea (without specifying):
Gulf: unsweetened black tea
Egypt and Levant: overly sweet and over steeped black tea (levant usually with mint).
West of Libya: green tea with one or two types of mint.