1st Battalion 4th Infantry Regiment would deploy part of its units starting in August 2004 and ended in January 2011. The Battalion maintained a reinforced infantry company as part of the International Security Assistance Force (ISAF).

2nd Battalion 4th Infantry Regiment was activated in 2005 as part of the 4th Brigade 10th Mountain Division and would immediately begin preparations for deployment to Afghanistan. In 2006 the Battalion would deploy to Afghanistan and demonstrate the will of the American soldier during numerous operations in the austere environment. The Battalion would be immediately called upon in 2007 to return to the combat zone but this time in Iraq to serve in the treacherous streets of Baghdad for 15 months. In 2010, the Warriors of 2nd Battalion would return to Afghanistan for another tour of combat against America’s enemies. In 2012, the Battalion would send the Battalion back into the fray once again to support Special Operations Forces. Then in 2014, two companies and the Battalion HQs would be sent to support operations in Afghanistan.  And in 2017, the Battalion would be sent to Iraq to assist in the retaking of Mosul from the ISIS fighters. In 2019, two companies and the Battalion HQs would be sent to the border with Mexico to assist in border security operations.

3rd Battalion 4th Infantry Regiment would be activated as part of the 170th Infantry Brigade Combat Team, Baumholder, Germany in 2009 and deployed in November 2010 to Regional Command Capital where it initially assumed part of the NTMA training mission in and around Kabul. The Battalion would redeploy to Baumholder, Germany in 2011 for deactivation in February 2012.