Military operations in Afghanistan are proving that the best precision weapons in the U.S. arsenal are soldiers on the ground, Army Chief of Staff Gen. Eric Shinseki told defense and industry leaders Thursday. In prepared remarks before a Washington conference sponsored by the Association of the United States Army, an Army lobbying group based in Arlington, Va., Shinseki said air strikes against Taliban and al Queda forces in Afghanistan have not been fully effective. Long-range precision strikes are a "great capability, but [they don't] solve the problem," Shinseki said. Precision weapons, such as laser-guided missiles and bombs, have never worked well against imprecise or mobile targets, and the U.S. reliance on them in military operations over the last several years may well have emboldened enemies of the United States to escalate their operations against the country, Shiniseki said. Ground forces are often the only way to attack "conflicted targets"-assets that are shielded in mosques or hospitals, for instance, where striking them will endanger innocent people, or targets that are difficult to find from the air, such as those in caves and deep bunkers, Shinseki said. "We must be able to attack conflicted targets with a variety of weapons without collateral effects. And right now, we cannot do this very well-and we never have," he said. Shinseki said the Sept. 11 terrorist attacks on the World Trade Center and the Pentagon have added urgency to the Army's ongoing plans to create several medium-weight brigades that are more powerful than its light infantry forces, yet more agile than its heavy-armored tank forces. U.S. tanks are the most lethal in the world, but can take months to transport to the battlefield. The first medium-weight brigade is to be fielded and operational in the spring of 2003, but Army officials are trying to speed that up by several months. The brigades are meant to solve a critical problem for the Army: It can't move sufficiently powerful forces to the battlefield in time for war. Its light infantry troops are too vulnerable to attack in most situations, and its heavy forces are too cumbersome to arrive on short notice. The new brigades will not be as powerful or invulnerable as tank units, but they will be vastly more lethal and more versatile than light-infantry units. The Army views the medium-weight brigades as an "interim force" that will fill its current gaps in capability while it seeks to meet its long-term objective of fielding units that are faster-moving, more powerful, and less vulnerable than anything currently in the inventory. What exactly that future force, known as the "objective force," will ultimately look like will depend largely on technology that is still under development, Shinseki said. Nonetheless, he intends to make transformation to such a force inevitable. He acknowledged critics-many within the Army itself-who say he is moving too fast to shift the Army away from its vaunted tank divisions, which were so critical in winning the Persian Gulf War. "Those who say we are going too fast endanger the Army's relevance to national security. It's no longer a matter of complaining that we're moving too fast or spending too much money on the development of new technologies," he said. "It's not a debate. The Army must change because the nation cannot afford to have an army that is irrelevant."