The fiscal cliff deal was a disappointment, but Republicans back home who view the deal as some sort of treachery have to be realistic about what was actually attainable.
Republican leaders in Congress were in an extremely weak negotiating position (in which they had put themselves). There was no chance that any deal was going to contain zero tax hikes and genuine spending cuts.
Considering the Republican position, the deal is far less economically harmful than it could have been. It makes permanent the Bush tax rates for the vast majority of Americans and makes it harder to raise rates on anyone in the future. It includes $600 billion in new revenue, which is $200 billion less than what House Speaker John Boehner offered earlier in December and $1 trillion less than what President Obama initially demanded.
True, it leaves spending and the debt to grow, and it failed to halt other automatic tax hikes. But no deal was going to fix the first two problems, and some tax hikes were inevitable with Obama in the Oval Office. Ultimately the deal makes it harder for Obama to demand more tax hikes on the wealthy if we ever get around to discussing real spending cuts and entitlement reform. The GOP's task now is to move forward with serious proposals to take both of those long overdue steps.