Commerce is simply one element of our pursuit of happiness, One of those rights. Not the whole. Not even the most important. To me, the right of freedom of speech, association, worship, to petition government for redress of grievans and freedom of the press are simply sine quo non. The first Amendment was first for a reason.
If you'll read the DOI I believe the subject is mostly commerce.
The government must also enforce legal contracts that we enter into with each other and provide for defense.