Here is a pdf of a 2005 Congressional Budget Office study of improved strategic mobility
It has options for buying more exising air transports like the C17 and more of the LMSR (Large medium speed roll on/roll off ships)
The more interesting options are the development of improved airlift and sealift systems. For airlift, they examine heavy lift hybrid airships, which are blimps that also have dynamic lift. The airships would have 500 plus ton cargo capacity with 80-120 knot speed (100knot average).
All programs were for about 11 billion total cost including development, procurement and operations.
The high speed ships they are examining are NAVSEA Trimaran concept with 55 knot/hour speed, 5000 ton payload capacity, 360 MW of installed power, 8,700 nautical mile range and 8 days to transit 10,000 nautical miles.
A near-term high speed ship with less technical risk with 45 knot/hour speed, 10,000 ton payload capacity, 250 MW of power, 5,000 nm range and 9 days to transit 10,000 nm.
A hydrofoil company that makes personal hydrofoils that can go at 100knots/hour has a design for a 100 knots/hour 300 person passenger ferry.