Hot Metal Rain

From the introduction:

After an Adrek Corporation Combat Cyberform became a rogue and went on a killing spree in Boston, the United States Government realized two important things. First, they realized that experimentation with things as dangerous as combat cyberforms could not be permitted to continue unsupervised. Second, combat cyberforms have enormous military potential that must be exploited by the United States before other nations. The US government gave Adrek two options: They could cease all cyberform experimentation or they could continue under careful government supervision. Faced with these options, Adrek took the second option.