Some of the statements in the abstract are self-contradictory; it is stated that because of "their ability to pass through all material without attenuation, HFGWs could be utilized for uninterruptible, very lowprobability-of-intercept (LPI), high-bandwidth communications" which is clearly contradictory since the HFGWs must interact with a receiver to be useful.I attempted to clarify this in the attached manuscript as follows:"Although HFGWs do not interact with and are not absorbed by ordinary matter, their presence can be detected by their distortion of spacetime as measured for low-frequency gravitational waves by the Laser Interferometer Gravitational Observatory or LIGO (Abbott, et al., 2008), Virgo (Ballardio, et al, 2001), GEO600 (Hogan, 2008) and for HFGWs by detection photons generated from electromagnetic beams having the same frequency, direction and phase as the HFGWs in a superimposed magnetic field, the LiBaker HFGW Detector (Baker, Stephenson and Li, 2008;Li et al., 2008;Li et al. 2009), by the change in polarization they produce in a microwave-guide loop as in the Birmingham University Detector (Cruise and Ingley, 2005) and by other such HFGW detection instruments (Chincarini and Gemme, 2003;Nishizawa et al. 2008). None of these effects utilized for detection represent interaction with matter in a way that causes GW absorption, but rather interaction with fields and the detection devices do not attenuate the GWs." The detection instruments measure change in GW polarization, distortion of the fabric of spacetime, change in EM that has the same frequency, phase and direction as the GWs, etc. -none of which attenuates the GW.Also, I believe HFGW propulsion is certainly very unlikely, and surveillance also is a non starter if one believes the very small cross-section for interaction with ordinary matter.Too many concepts in the history of Science have been ruled out prior to actual experiments. Conventional propulsion applications of GW have been discussed theoretically by Bonnor and Piper and by Davis and from an astrophysical viewpoint by Bekenstein. The most compelling discussion is found in Landau and Lifshitz where they note qualitatively the possibly significant influence of high-frequency gravitational waves on otherwise static gravitational fields --certainly a possibility that calls for experimental study. Surveillance applications would depend upon the so-far unknown influence of intervening matter between the HFGW generator and detector in a laboratory experiment (no absorption though) and represents a motivation for such an experiment as stated in the manuscript. The following quotes from the manuscript amplify this idea: "These important potential HFGW applications are motivations for HFGW research and development and such an R&D program is recommended for immediate initiation." "The plausibility of the theoretical applications cannot, however, be adequately determined until after a proof-of-concept test is successfully completed." "A quantitative analysis must necessarily await a laborat...
