Yeah, declaring war is only more than just words insofar as there are laws that require a declaration before certain activities or uses of powers.

Congress has allowed the president and executive branch agencies to strike other countries, kill non combatants and soldiers, occupy countries, kill Americans, and operate torture sites without needing a formal declaration of war. There are several relevant acts of Congress, but the clearest example is the Authorized Use of Military Force. We're still using it 25 years later and Congress keeps reauthorizing it and allowing more and more broad interpretations.

We invaded Afghanistan, Iraq, and bombed several more countries in retaliation for 9/11