As President Bush weighs the pros and cons of waging war on Iraq, the issue of U.S. oil energy security looms large. And although no one would have believed it 50 years ago, the U.S. is increasingly contemplating Russia as a stable and desirable alternative source of oil. The strategic partnership between the Cold War-era enemies would be built on mutual self-interest; the U.S. wants an oil source far from the strife of the Middle East, and Russia wants to rebuild its economy and enhance its importance in global politics. The Middle East, and particularly Saudi Arabia, still dominates the oil market, but Russia is already in second place. One hot spot of Russian energy development: Sakhalin, a verdant island in the far eastern Sea of Okhotsk. The region could yield 3.3 billion barrels of oil and lots of natural gas — but environmentalists worry that energy exploitation on Sakhalin could harm the area’s rare gray whales, one of just two populations left in the world.