Secretary of State Hillary Rodham Clinton said Friday that U.S. officials were “taking all necessary steps” to deal with the possible terrorist threat that emerged late this week, but she warned against allowing obsessive fear of terrorism to undermine the nation’s core values or drive Americans into isolation.

In a policy speech marking the 10th anniversary of the Sept. 11, 2001, attacks, Clinton said that while the nation had at times veered off course over the past decade, “we are determined not to let the specter of terrorism darken the national character that has always been America’s asset.”

“We cannot afford to live in fear, sacrifice our values, or pull back from the world,” Clinton told an audience at New York’s John Jay College of Criminal Justice. “Closing our borders, for example, might keep out some who would do us harm, but it would also deprive us of new entrepreneurs, ideas, and energy.”

Clinton outlined a long-term vision for defeating terrorism that integrated military operations with law-enforcement and what she called “smart-power” statecraft: diplomacy and targeted foreign aid intended to enhance global cooperation against terrorism and diminish the appeal of al-Qaeda and allied groups. She said the United States should “not shy away from using military force” to attack terrorists’ safe havens, but she argued for a more robust use of law-enforcement tools as well as the courts — both civilian and, “where appropriate, reformed military commissions.”

Equally important, she argued, were strong international partnerships, both governments and civil-society groups that cooperate on information-sharing and in countering terrorist propaganda. Clinton credited the administration’s efforts to improve the country’s image abroad and to work cooperatively within global organizations. “This is not about winning a popularity contest, but it’s a simple fact that achieving our objectives is easier with more friends and fewer enemies,” she said.

Clinton touted the proposed Global Counterterrorism Forum, to be formally launched next month, as a model for international cooperation in fighting terrorism. The forum will involve nearly 30 countries, including Muslim nations, and will be co-chaired initially by the United States and Turkey.

“Together, we will work to identify threats and weaknesses, devise solutions, mobilize resources, and share expertise and best practices,” Clinton said.

Even in an era of tightening budgets, international cooperation against terrorism will continue to require U.S. aid to developing countries to create economic opportunities and strengthen governance, she said.

“We will certainly not solve all the problems of every failed state – nor should we try,” she said. “But if we can make it harder for al-Qaeda to fill its ranks and coffers, while ramping up pressure from new and more effective partners, that will make a real impact.”