My guess would be that you lack the range, and the red areas show places you can't move through because they're too far from a naval base. There's a wall of red between California and the Philippians, so you can't make the trip.
The easiest/quickest thing to do would be to stick it in a fleet with a larger ship or ships, which will result in a combined fleet range range between the short range of your destroyer and the longer range of the bigger ships.
IIRC, the tooltip for naval bases also says that bigger naval bases equals more range, although I'm not sure how that works. Naval bases take a while to build anyway, so that won't help you in the short term.
The easiest/quickest thing to do would be to stick it in a fleet with a larger ship or ships, which will result in a combined fleet range range between the short range of your destroyer and the longer range of the bigger ships.
IIRC, the tooltip for naval bases also says that bigger naval bases equals more range, although I'm not sure how that works. Naval bases take a while to build anyway, so that won't help you in the short term.