Complex sentence: Alexander contends that the Reagan administration's 1982 escalation of the "War on Drugs" purported to be a response to a crack cocaine crisis in black ghettos, however it was announced well before crack cocaine arrived in most inner city neighborhoods.
Split into simpler sentences: Alexander contends that in 1982 the Reagan administration began an escalation of the "War on Drugs," purportedly as a response to a crack cocaine crisis in black ghettos. However this escalation was announced well before crack cocaine arrived in most inner city neighborhoods.