[1] Search Query Terms
This graphs shows only that of people including the phrase “nuclear war” in a Google query (between the beginning of 2004 and late April 2011) there was a gradual but marked decline during the period. It does not say what proportion of all queries included “nuclear war”, nor anything about the absolute number of such queries. It does seem to show a small upward bump about the time of the 11 March 2011 earthquake and tsunami initiating the chain of events at Fukushima Daiichi.
North Korea announced a first nuclear test on 9 October 2006. A second test took place 25 May 2009. The peaks of the graph appear to coincide with those events.
[2] Search Results
[All numbers are approximate: “about ... ”"]
10,400,000: IAEA IAEA
5,100,000: WMD "weapons of mass destruction"
1,230,000: Nuclear Disarmament "nuclear disarmament"
283,000: Gorbachev "mikhail gorbachev" nuclear "by the year 2000" [advanced search: all three strings in page]
207,000: Denuclearization denuclearization
196,000: Abolish "abolish nuclear weapons"
151,000: Global Zero "Global Zero" nuclear
99,600: Four Horsemen shultz perry kissinger nunn
25,400: ICNND "international commission on nuclear nonproliferation and disarmament"
24,000: Obama "I state clearly and with conviction america's commitment to seek the peace and security of a world without nuclear weapons": from Barack Obama's speech in Prague, 5 April 2009
18,500: NPT Article VI "Each of the parties to the treaty undertakes to pursue negotiations in good faith on effective measures", beginning of Article VI of the NPT
6780: Ban Ki-Moon: "ban ki moon" "five-point plan" [advanced search: both strings in page]
3,880: IPFM IPFM fissile [advanced search: both strings in page]
NOTES
[Note 1] Google Trends: http://www.google.com/trends