The top U.S. diplomat in Iraq said Thursday that Baghdad was making some political progress but faces considerable difficulty in trying to heal a nation long gripped by violence."If there is one word, I would use to sum up the atmosphere in Iraq -- on the streets, in the countryside, in the neighborhoods and at the national level -- that word would be fear," Ryan Crocker told the Senate Foreign Relations Committee. Crocker testified by video link from Baghdad. He also warned lawmakers against relying heavily on a list of benchmarks to measure gains made in Iraq. Earlier this year, Congress asked the White House to report on progress made in 18 target areas for political, security and diplomatic reforms; last week, the administration reported mixed results."The longer I am here, the more I am persuaded that progress in Iraq cannot be analyzed solely in terms of these discreet, precisely defined benchmarks because, in many cases, these benchmarks do not serve as reliable measures of everything that is important -- Iraqi attitudes toward each other and their willingness to work toward political reconciliation," Crocker said.Crocker's image was transmitted onto several large flat-panel screens, including one sitting on the witness table facing the senators. He faced a tough crowd. A majority of the senators on the Foreign Relations Committee, including six of the 10 panel's Republicans, have expressed serious doubts about President Bush's decision to deploy additional troops.