National technical means of verification (NTM) are monitoring techniques, such as satellite photography, used to verify adherence to international treaties.
At first, the phrase reflected a concern that the "Soviet Union could be particularly disturbed by public recognition of this capability [satellite photography]...which it has veiled.".
Measurement and Signature Intelligence (MASINT) techniques, many being especially obscure technical methods, are extremely important parts of verification.
While the techniques here are focused primarily at missile and nuclear weapons limitation, the general principles hold for verification of treaties to counter the proliferation of chemical and biological warfare capabilities: "trust but verify".
[2] The methodology he describes for counting missiles moving into Cuba, emplaced there, and later removed are direct parallels to the way in which imagery is used for verification in arms control.
TELINT is one of the "national means of technical verification" mentioned, but not detailed, in the Strategic Arms Limitation Treaty (SALT).
This data can provide valuable information on the actual performance of the missile and especially its throw-weight, i.e. the potential size of its nuclear warheads.
The SALT I treaty language [3] "the agreements include provisions that are important steps to strengthen assurance against violations: both sides undertake not to interfere with national technical means of verification.
"it involves phenomena transmitted through the earth (ground, water, atmosphere) and manmade structures including emitted or reflected sounds, pressure waves, vibrations, and magnetic field or ionosphere disturbances.
In 1960, George Kistiakowsky introduced the "threshold principle" that balances the needs of arms control with the realities of seismic verification.
The CTBTO will operate an International Monitoring System (IMS) of MASINT sensors for verification, which include seismic, acoustic, and radionuclide techniques.
"[10] Advocates of the CTBT [11] Paine argues "...there is recent demonstration that the IMS will be able to detect and identify non-evasive explosions of less than 1 kiloton in some strategically important areas."
These include infrasound microbarographs (acoustic pressure sensors) that detect very low-frequency sound waves in the atmosphere produced by natural and man-made events.
The US and Russia have agreed to have, under controlled conditions, inspectors from the other side physically examine locations at which a forbidden nuclear test, possibly below other detection thresholds, may have taken place.
The Director of DTRA is also "dual-hatted" as the head of the Center for Combating Weapons of Mass Destruction (SCC WMD), an agency of the US Department of Defense's Strategic Command.
[16] After Algerian independence, France moved its test range to French islands in the Tuamoto Archipelago in the Western Pacific.
Upon that notice, KC-135R tankers, temporarily modified to carry MASINT sensors, would fly around the test area, as part of Operation BURNING LIGHT.
U-2R aircraft, in Operation OLYMPIC RACE, flew missions, near Spain, to capture actual airborne particles that meteorologists predicted would be in that airspace [18] BURNING LIGHT, the airborne EMP and cloud photography program, was the manned aircraft portion of a larger Defense Nuclear Agency program called HULA HOOP (1973 name) and DICE GAME (1974 name).
Another portion of this program involved a US Navy ship, in international waters, that sent unmanned air sampling drones into the cloud.