I think that such agreements can be one tool if they are in fact enforced.
As an example, when the executive order on Privacy Act protection being removed from non-citizens was passed, the ACLU sent a letter to the European Parliament and the European Commission letting them know that U.S. assurances under pending agreements with the EU may be called into question now because those agreements that permitted data sharing between the EU and the U.S. relied on certain protections and guarantees of how information would be retained, and limiting access and limiting its use.
Certainly we think that if those agreements exist, they should be enforced, and particularly if those agreements form the basis for the information sharing.