 Complete the following phrase:  Following Obamas election, many pondered the existence of a postracial America. However, lingering racial tensions quickly became apparent, and many African-Americans expressed outrage over what they saw as racial venom directed at Obamas presidency. In July 2009, prominent African-American Harvard professor Henry Louis Gates, Jr., was arrested at his Cambridge, Massachusetts home by a local police officer, sparking a controversy after Obama stated that the police acted stupidly in handling the incident. To reduce tensions, Obama invited Gates and the police officer to the White House in what became known as the Beer Summit. Several other incidents during Obamas presidency sparked outrage in the African-American community andor the law enforcement community, and Obama sought to build trust between law enforcement officials and civil rights activists. The acquittal of George Zimmerman following the killing of Trayvon Martin sparked national outrage, leading to Obama giving a speech in which he noted that Trayvon Martin could have been me 35 years ago. The shooting of Michael Brown in Ferguson, Missouri 