In the article, she quotes Harvard physicist Paul Horowitz as saying:

"Statistically, it is extremely unlikely that our fist contact with an ETI [extra-terrestrial intelligence] civilization will also be its first contact with an ETI civilization. Thus the advanced technology we detect will have experienced this type of encounter many times before. It already may have established a galactic protocol for information interchange, to which ab initio transmissions by Earth will have no chance of adhering. Thus we justify our asymmetrical listen only strategy by recognizing our asymmetrical position amongst galactic civilizations. We are among the very youngest!"