Mattis Discloses Part of Afghanistan Battle Plan, but It Hasn’t Yet Been Carried Out David W. Barno, a retired Army lieutenant general, who led the war effort in Afghanistan for almost two years, said the changes probably indicate that the American military is shifting from a largely defensive war and "getting off its hands and much more involved in combat operations." Indeed, Mr. Mattis’s push to implement more aggressive rules of engagement coincides with his decision to place American troops closer to the fighting, which he stresses will be in only an advisory role. Pressed by lawmakers, including Senator John McCain, Republican of Arizona and the chairman of the Armed Services Committee, about the Pentagon’s failure to provide more details about the Afghanistan war plan, Mr. Mattis divulged new information about more aggressive rules of engagement there. Mattis said that You see some of the results of releasing our military from, for example, a proximity requirement — how close was the enemy to the Afghan or the U.S.-advised Special Forces, "It’s a bit odd to me they didn’t go down that route to paint the picture more clearly." Later during the hearing, Mr. Mattis was pressed by Senator Kirsten Gillibrand, Democrat of New York, about another issue: whether he would be "honest with the American people about the numbers of troops you are sending over and what their missions will be." Mr. Mattis replied, "No, ma’am, if it involves telling the enemy something that will help them." Eric Schmitt contributed reporting. An American military official in Afghanistan said that Gen. John W. Nicholson Jr., the top American commander in the country, had requested the new rules, and that they were expected to be in effect soon.