In a heavy saucepan, bring the water, oil, salt and pepper to a boil over high heat. Gradually whisk in the cornmeal. Bring the mixture back to a boil, stirring frequently. Reduce the heat to low and simmer slowly, stirring frequently, until the polenta is thick, about 18 minutes
While the polenta is cooking, prepare the shrimp: In a large fry pan over medium heat, warm the oil. Add the onion, garlic and red pepper flakes and sauté until the onion is translucent, about 5 minutes. Add the wine and boil until it is reduced by half, about 4 minutes. Add the tomatoes with their juices. Simmer until the sauce thickens slightly, breaking up the tomatoes with a wooden spoon, about 10 minutes.
Add the wine and boil until it is reduced by half, about 4 minutes. Add the tomatoes with their juices. Simmer until the sauce thickens slightly, breaking up the tomatoes with a wooden spoon, about 10 minutes.
Sprinkle the shrimp lightly with salt and black pepper. Add to the fry pan, turn to coat with the sauce, cover and simmer until almost cooked through, about 2 minutes each side. Mix in the olives, capers and thyme and simmer until the shrimp are cooked through, about 30 seconds. Taste and adjust the seasoning.
When the polenta is done, stir in the thyme. Divide the polenta between 2 warmed plates, spreading it out in a circle. Spoon the shrimp and sauce over the top and serve immediately.