However, it is a self-certification program and it isn't really a US law, just a regulation enforced by the FTC. So while it should protect your data from third parties, e.g., being sold to advertisers, etc., it most likely does not protect your data from the US government.
the Safe Harbor asks compliance with the Data Protection Directive which is supposed to become obsolete in the following few years. Not to mention that it's apparently opt-in, which is basically useless.
However, it is a self-certification program and it isn't really a US law, just a regulation enforced by the FTC. So while it should protect your data from third parties, e.g., being sold to advertisers, etc., it most likely does not protect your data from the US government.