How to support the "Obama Stimulus Package?"?

I have to do a debate soon on the affirmative side of the Obama Stimulus Package. It's not a formal debate, and each side will have about 10 speakers. We had a meeting already and have distributed our roles. I'm igned to support the package by saying that if the U.S.'s economy fails, so will other nations of the world. I know this isn't a very strong statement, so I need some help on it. Maybe some evidence or extremely good points? Thanks so much!