We in the states may need to deal with our past as a nation (American chattel slavery is historically one of the most violent and oppressive forms of slavery, if not the most), but that should not take away the overall focus on modern slavery. Dealing with American slavery is more of the US as a whole coming to terms with the blood we shed and admitting mistakes to assist with dealing with current and other past mistakes and more importantly stop future mistakes, while dealing with modern slavery is about more about ending the bloodshed. When talking US racism and various social issues (such as redlining), then discussing US slavery makes sense. When talking about the current global slavery market, then we have to look at it at a global level. People learn about historical horrors to avoid those mistakes. People can also deal with their nation's past while also dealing with the global present and future.