In a medium saucepan, cover the barley with water and bring to a boil. Cover and simmer over low heat, stirring occasionally, until the barley has split and is tender but still slightly chewy, about 45 minutes. Drain the barley and transfer to a bowl.
Wipe out the saucepan and heat 1 1/2 tablespoons of the oil in it. Add the onion and cook over moderately low heat, stirring, until tender, about 5 minutes. Add the tomatoes and cook over moderate heat until their juices thicken, about 4 minutes. Add the garlic and cook until fragrant, about 2 minutes. Add the cumin, coriander, cinnamon, cayenne and cloves and cook, stirring, until fragrant, about 3 minutes. Add the barley and the water, cover and simmer over low heat until the flavors are nicely blended, about 4 minutes.
In a large skillet, heat the remaining 2 tablespoons of oil until almost smoking. Add the okra and cook, turning once, until browned on both sides, about 6 minutes. Season the okra with salt and stir into the barley. Season the barley with salt and serve hot.
Make Ahead: The recipe can be prepared through Step 2 and refrigerated for up to 2 days. Bring back to a simmer before proceeding.
Wine Recommendation: This spice-rich vegetable stew warrants an equally spicy red with a texture to match. A California Zinfandel, such as the 1996 Ridge Sonoma Station or the 1996 Turning Leaf, is just right, particularly if the stew accompanies a hearty meat dish.