I don't think just because the game is from Japan, that makes it a JRPG. That's not a good way of thinking, but too many people view it that way.
JRPGs originated in Japan yes, but now the term has come to mean a style of game, just like Platforming or FPS. Yes, level grindiing, story are certainly RPG elements, but you can find those elements in many other games today thanks to advancements in technology.
What makes a JRPG, is the style. Most JRPGs make you play a set protagonist (not "you"). You follow this character through the story, and often this character makes his/her own decisons throughout the game. This allows developers to create a carefully crafted story, since they don't have to worry about player choice so much. Also, they more commonly use menu combat, but i'm not sure if thats a deciding factor.
WRPGs i believe focus on fantasy. What i mean is, they try to place you into a world where you can be totally immersed into the world. You can express yourself however you want. Character creation, skill trees, dialouge choices, choosing a class, customizing gear. This is expression of self, a lot more common in WRPGs.
Then there are obvious reasons they are both RPGs, such as maybe having an overworld where you can battle creature(Ni No Kuni) or maybe turn-based combat based on strategy of using elements (persona).
A JRPG can come out of the west(seppteracore), and a WRPG style game can come out of Japan (dragon's dogma, dark souls). The labels JRPG and WRPG are poorly chosen, and just confuse people.