The struggle for control of TNK-BP is the first big test for Tony Hayward's leadership of BP. Since taking over as chief executive from Lord Browne a year ago, he has focused on reforming the company's structure and operations, to cut costs and raise performance. The threat to BP's future in Russia is forcing Mr Hayward to take on a huge strategic challenge as well. There are good reasons for him to hope that he can achieve at least a qualified success. BP needs Russia but Russia also needs companies such as BP. If Mr Hayward fails, however, BP will face a much darker future.