Does strong government help?

The comment thread on this piece is well worth reading.  In the piece, itself, Noah Smith is pointing out a possible reason for people to adhere to libertarianism -- the concern over the state protecting people from small group actions.  While this is not the only issue with this creed, I do want to look at it another way.

Why did primitive cultures lose to organized cultures?  It is pretty clear, for example, that the Gauls had a much less intrusive government than the Romans.  They had a lot of brave fighters and a fairly free society (as ancient world societies went).  While certainly a bit romanticized in literature, it is clear from reading Julius Caesar's accounts of his wars that strong central government was notably absent from the Gauls.

So why were they overrun by a high-tax society with a strong central government?

It is equally interesting to ask questions like why the residents of the American West sought statehood.  After all, did they not have a much freer society outside of the United States?

Or why do people seem to suffer so badly in failed states, which also have a lack of strong central government?

I think that these practical concerns need to be addressed.  A lot of what the state does is either protective (banning force and fraud) of individual citizens, a vehicle to allow disputes to be settled (the courts), acting as an insurance company for risks that are hard to use markets for, providing public goods, and mutual defense.  Perhaps the goal of government should be effective government and not minimalist government.

I wonder if libertarianism thrives because most of us have not seen a failed state in the first world?  People have a lot of mobility (if they are rich) and so there is less of a sense of how the government helps make a society function.