I saw the phrase “touched off a scramble” in the article titled “Redefining headphone, with more bass” in the New York Times (November 20) followed by the following copy:
“The rap impresario Dr. Dre is behind Beats, a successful line of expensive headphones that have become a fashion accessory and touched off a scramble in the industry.”
There were other instances of using this phrase, for example:
The authorization for establishing three of the satellite offices touched off a scramble among members of Congress who want one in their states or districts. - www.statesman com
The prospect of nearly $1 trillion in cuts unnerves military leaders, troubles lawmakers protective of the Pentagon and has touched off a scramble in the defense industry as contractors look to spare their multibillion-dollar weapons programs. – www.thinkownusa.com
There is no entry of “touch off a scramble” in any of Oxford, Cambridge and Merriam-Webster online dictionaries, while Google Ngram Viewer shows the usage of “touched off a scramble” that (suddenly) started in circa 1940, peaked around 1980, and since then is dropping down sharply.
I understand “touch off a scramble” means “cause a commotion or sensation.” Am I right? Is it an idiom, or the simple combination of “touch off” and “scramble”?
Is this expression actually losing vigor as the Google Ngram curve indicates?