IMO, a different perspective on the relationship between Haiti's Catholicism and its Voudoun (I prefer that to "voodoo," which has so many negative connotations thanks to prejudicial reporting and portrayals) can be found in Tom Faw Driver's book: "Liberating Rites: Understanding the Transformative Power of Ritual." He begins by exploring a vibrant nature-mystical ritual, led by a very involved Voudoun priest, and comparing it to a rather lifeless Catholic (or perhaps Anglican, I don't remember) ritual led by a Catholic priest, and from the comparison draws worthwhile lessons.
I don't cite this to elevate Voudoun above Roman Catholicism, but only to say that either religion can have shallow and deeper versions, richer and poorer applications, magical thinking or mystical depth. But I would hasten to add that Christians in general have not given "pagan" / earth-based religions their due; have been highly prejudicial toward them. The task ahead is to take each religion to its deepest (highest) levels, let them work together on the practical tasks of rebuilding Haiti's infrastructure, and let them spark growth in each other through dialogue.
A possible comparison of the relationship between these two religions is the comparison with Buddhism and Shinto in Japan, where Buddhism was the "intruder." But for the most part, those two religions have established some fertile interaction.
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