From: The Closed World by Paul N. Edwards, copyright 1996 Massachusetts Institute of Technology; Pages 87 and 88, beginning with paragraph 3:
By 1948 Air Force Intelligence-contrary to the estimates of both Army and Navy intelligence services and those of the Central Intelligence Agency-had come to believe strongly in the possibility of imminent Soviet attack. This view bordered on the bizarre. Such an attack would have required (a) the Tu-4 Bull long-range bombers demonstrated for the first time in a 1948 Soviet air show and not produced in any quantity until the following year (b) a suicide-mission strategy, since the Tu-4 could hold enough fuel to reach the United states from the USSR, but not to return, and, most absurdly, (c) the USSR's willingness to risk American atomic retaliation at a time when it possessed only conventional weapons.
The strange 1948 emergency alert provides good evidence of the strength of these implausible assumptions. In March of that year, USAF Headquarters ordered the existing skeleton emergency air defense system onto 24-hour alert. The alert lasted nearly a month, until it was suddenly cancelled in mid-April
Source: Central Intelligence Agency, "Memorandum For: The Director of Central Intelligence, Subject: CIA Relations with the Air Force on Estimates of Soviet Intentions, Page 5, item 8.,
We have certainly never seen any Air Force estimate that could be described as likely to involve this country in war nor did we see any estimate on Soviet intentions to attack Scandinavia as reported by Alsops. It is quite true, however, that at the time of the preparation of the 60 day estimate for the second meeting of the IAC Directors and of ORE 22-48, the Air Force elements were far more alarmist than any of the others.
Bob note: The 60 day estimate was begun after General Clay's cable on the 5th, which started the "March War Scare". Office of Reports and Estimates (ORE) report 22-48 [Soviet Resort to Direct Military Action during 1948, a Special Report of Joint Ad Hoc Committee] was completed 2 April 1948. The inference about the Air Force being alarmists accounted for time that included the 25 March date. A further demonstration of this on-going concern, forced by Air Force alarmists, being looked into, can be seen in the March 25, 1948 Memorandum From: Chief, FBIB (Foreign Broadcast Information Bureau), To: Chief, Editorial Division, Chief, Field Division, Chief, Special Reports Division, Liaison Officer, Chief Officer, Administrations Officer, Subject: Progress Report for Month of March, 1948,
It is desired that you furnish me not later than noon, Thursday, April 1, 1948* an informal memorandum estimating any information pertaining to your Division that should be included in the Monthly Report for the month of March, 1948. signed L.K. White
* 1 April was the day before ORE 22-48 was to be published
Bob Note: No other historical piece uses the March 27th date and since we have reference to the Interoffice Memorandum, between General Anderson and General Timberlake, written on the morning of the 25th, we can be certain that the 25th is the correct date.
From: Searching the Skies, the Legacy of the United States Cold War Defense Radar Program, by United States Air Force, Air Combat Command, June 1997 Authors credited: David F. Winkler and Julie L. Webster Performing Organization: U.S. Army Construction Engineering Research Laboratories (USACERL) Special Report 97/78
The Evolution of Air Defense (1918-1959), Page 17:
As Project SUPREMACY was undergoing consideration, relations with the Soviet Union continued to sour. In February 1948, there was a Communist coup in Czechoslovakia. In China, Communist forces continued to gain ground against Chiang Kai-shek. Air Force intelligence warned that the Soviets were preparing to conduct a surprise attack. On March 27, 1948, General Spaatz, concerned about the vulnerability of the Atomic Energy Commission plant at Hanford, Washington, ordered the recently placed ADC radars at Arlington, Spokane, Neah Bay, and Hanford, Washington, and at Portland, Oregon, to begin operating on a 24-hour basis. Due to insufficient personnel and material resources, round-the-clock operations in the northwest proved beyond ADC's capability. Despite these problems, ADC was ordered to take AN/CPS-5 and AN/TPS-1B/1D radar sets out of storage for operation in the northeast and in Albuquerque, New Mexico.
The following quote, from the most reliable source, is offered to show the stress felt and expressed dealing with air interceptions.
The Emerging Shield by Kenneth Schaffel
After a ten-day exercise in the northwest early in 1949 proved the competence of weapons controllers and air crews to perform successful intercepts, Whitehead authorized his air commanders to begin active air defense to the limit of the capabilities of their forces. This was possible because Saville had previously initiated arrangements with the Civil Aeronautics Administration and Military Flight Service to provide flight plan data to the 25th Air Division in the northwest and the 26th on the east coast. The respective control centers received prompt information when bomber-type aircraft penetrated the divisions' active defense zones. Now, under Whitehead's orders, the 25th and 26th air divisions attempted to intercept tracks that could not be identified positively by flight plan correlation. The aircrews received orders to shoot down violators of airspace over the atomic plants in Hanford, in Oak Ridge, and in Los Alamos, New Mexico, if those violators committed a blatantly hostile act such as dropping bombs or paratroopers, or firing on interceptors and ground targets.54
Headquarters USAF, however, concerned about possible errors, such as the shooting down of civilian aircraft, decided that Whitehead had moved too fast. On January 17, 1950, he received orders to cease all interception operations.
54 Sp rept, HQ USAF, Observation on Exercise Drummer Boy (Nov 4-14), Dec 2, 1949, HQ ADC, A Decade of Continental Air Defense, 1946-1956 (1956)