Crises spark off a wide variety of communicative activities; extant research documents the critical role of the community during crises. The terrorist attacks of September 11 fundamentally challenged the very fabric of American society. How did Americans respond to the crisis posed by the terrorist attacks of September 11 in their communicative choices? Based on the theory of channel complementarity, this article argues that individuals who participated in online communities to post and read thoughts about the attacks were also more likely to participate in real communities. An analysis of the data gathered by the Pew Center immediately after the 9/11 attacks demonstrates support for the theory of channel complementarity in the realm of community participation.