If it's unconstitutional, we don't need new laws to fix it. The existing laws (the constitution) need to be enforced. It's a failure of the judiciary, not the legislative branch.
The Judiciary must show reasonable deference to Congress when it comes to defining such things as "due process". If Congress chooses to create a due process in which it seems very easy for the Executive to get its way (e.g. the FISA court), on what legal basis is a sitting judge supposed to stand in the way? Unless it is completely obvious by existing legal precedent, a federal judge might rightly suppose it is the job of the Appellate and SCOTUS to define any new yardsticks.
FISA courts, PRISM, NSA, drone assassinations,... Congress holds in their hands the power to define the terms of the debate. That they choose not to is simply because the minority and majority leadership in both houses of Congress more greatly fear having to explain their own position to the American people, than they fear any particular arguable abuse by this president.
There will also be fights about how 'public' data is, and there will be arguments about how anything shared on Facebook falls under the definition of 'public data.'
Congress chooses not to, and that is implicit acceptance by the majority and minority leadership in both houses of Congress.