In 2007, nearly 300 university presidents across the United States signed a join statement denouncing the boycott movement. Following Operation Cast Lead in 2010, a group of 15 American university professors launched a campaign calling for an academic and cultural boycott of Israel. In 2010 the US Campaign for the Academic and Cultural Boycott of Israel (USACBI) announced it had collected 500 endorsements from US academics for an academic and cultural boycott of Israel. The endorsements were seen as a sign of changing US attitudes toward Israel in the wake of an Israeli raid on a humanitarian aid flotilla in the Mediterranean.