The Coast Guard has issued a “Request For Information” (RFI) about Land Based, Long Range/ultra-long endurance UAS (unmanned aerial system). You can see it here. The CG-9 commentary about it is here. The Coast Guard is being pushed in this direction by the Congress, specifically by the House sub-committee that has oversight of the Coast Guard.
Note this seems to be directed specifically at drug interdiction rather than Maritime Domain Awareness of approaches to the US coast.
There is specific reference to the UAS operating beyond line of sight, so it will require both some degree of autonomy and satellite communications.