Any legal system must be capable of carrying out three functions: 1) writing laws (typically done through legislatures), 2) adjudicating laws (typically done through the courts), and enforcing laws (for example, through the use of police). It is generally acknowledged that international law is not as strong as national law because its great ineffectiveness in carrying out one of the three functions described above. Which is it? Why does this weakness hamper the effectiveness of international law?