Certainly in the recent past economics prompted much violence, the Cold War and WWII being the best examples I can think of. And yet, throughout history religion has sparked an abundance of violence as well (the Crusades, various inquisitions, anti-Semitism, etc.). But the question addresses the here and now, not of the past.
You are comparing all secular wars to all religious ones
Anyway, the Cold War was ideological and over power, not resources.
But when it comes to economics, are there any major wars right now motivated by economic gains or conflicting economic paradigms more harmful than those sparked by religion?
Iraq's invasion of Iran and Kuwait were entirely motivated by the desire to seize their respective oil supplies. Modern way trade wars are rare though.
Also, how easy is it really to separate the two factors motivating conflict and determine which is the more decisive one?
Well, finding the justification is easy- seeing what is in a persons mind? Not so much.
Certainly, both religion and economic concerns were motivating factors in many wars, such as the conquistadors and later Western imperialists.
A bigger goal was prestige- competing with the other European powers or elevating your station in the nobility. Lets not forget sex and power- mestizos exist for a reason you know.
I would love to see relevant, modern examples of each promoting violence and disunity in our world.
Religion by its very nature promotes disunity. Economics is too vague to say- do they mean greed?
Make trade not war has always been my saying for world peace. When you trade with someone it immediately implies there's something they have that you want, and that you're respectful enough that you wish to embark on a transaction that will benefit the both of you. Over time it's not just goods that get traded but also ideas, cultural barriers break down and people respect each other a lot more. War breeds violence, and trade breeds peace, because only in peace is trade truly profitable.
The first world wars were trade wars. Having a monopoly on the spices was enough to make a nation fabulously wealthy and countries were spill large amount of blood to insure that. Modern trade is less bloody, but it has not always been so.
Religion can cause wars, especially these modern desert
You forget most state religions (the king is a god), ones with human sacrifice and the demand for flower wars and ones that consider warfare sacred (sects of Hinduism and Buddism).
These kinds of religions build up cultural barriers and the fundamentalists create a brush heap of paranoia and fear of anything different. In this scenario war becomes inevitable, and the Crusades are always the best example of this.
Not really. The Crusades were hardly inevitable. They wouldn't have happened without the Sejuck Turks plunging into the Byzantine Empire. A better example would be Muslim expansionism after the founding or Christian suppression of heretics, both made essential by the logic of the religion.