The ready force includes members of the 82nd Airborne Division and 18th Airborne Corps at Fort Bragg, North Carolina, and troops with the 101st Airborne Division from Fort Campbell, Kentucky. The alert order also included units at bases in Arizona, Texas, Washington state, Louisiana, Georgia and Ohio.
"These units, all told, include medical support, aviation support, logistics support and, of course, combat formations," Pentagon spokesman John Kirby said during a briefing with reporters.
The bulk of the troops could be called up as part of the NATO Response Force -- a multinational land, air, maritime and special operations force of 40,000 that could be activated by the alliance. For now, no deployment has been ordered, and the U.S. and its European allies are still hoping to dissuade Russian President Vladimir Putin from any imminent invasion of Ukraine using the 100,000 troops he has amassed near the country’s border.
"We still don't believe that there's been a final decision by Mr. Putin to launch another invasion. We still believe here at the department that there is time and space for diplomacy," Kirby said.
Secretary of State Antony Blinken said Wednesday that he had delivered a written response to Russia that laid out a "serious diplomatic path forward should Russia choose it." He called on Putin to end his aggression toward Ukraine, stop inflammatory rhetoric and make a serious effort at talks on European security.
A resolution to the crisis seems nowhere in sight, as Russia hasn't wavered on its demands for assurances that Ukraine will never be admitted to the NATO alliance and the removal of alliance forces from Europe's eastern flank.
The bases that could send troops to Europe for a NATO mission are: Fort Bragg, North Carolina; Fort Campbell, Kentucky; Fort Carson, Colorado; Davis-Monthan Air Force Base, Arizona; Fort Hood, Texas; Joint Base Lewis-McChord, Washington; Fort Polk, Louisiana; Robins Air Force Base and Fort Stewart, Georgia; and Wright-Patterson Air Force Base, Ohio.
On Monday, Defense Secretary Lloyd Austin ordered units at those bases -- a total of 8,500 troops -- to be on heightened alert for a rapid deployment. Kirby said the total number of troops could grow, depending on the mission and the unfolding crisis.
Additional troops and units already based in Europe under Gen. Tod Wolters, head of U.S. European Command, could also be moved east to deter or counter Russia, according to the Pentagon.
Putin began his buildup around Ukraine in March 2021 and has continued to add forces along its border and in neighboring Belarus in recent weeks. He ordered the invasion and annexation of the Crimea peninsula from Ukraine in 2014, drawing international condemnation and sparking an increased urgency in the U.S. to bolster forces on the continent.
-- Travis Tritten can be reached at email@example.com. Follow him on Twitter @Travis_Tritten.