This is not a SFW instance. NSFW communities will be tagged, and efforts will be made to keep SFW communities clean, but proceed at your own comfort level.
And you’d be wrong, it is high efficiency and high trust
The Orion concept offered both high thrust and high specific impulse, or propellant efficiency: 2,000 pulse units (Isp) under the original design and an Isp of perhaps 4,000 to 6,000 seconds according to the Air Force plan, with a later 1968 fusion bomb proposal by Dyson potentially increasing this to more than 75,000 Isp, enabling velocities of 10,000 km/s.[8] A moderate-sized nuclear device was estimated, at the time, to produce about 5 or 10 billion horsepower.[6][14]
And you’d be wrong, it is high efficiency and high trust
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)