We support the troops for protecting our freedoms, and then we break their heads for actually using them? Iraq war vet Scott Olsen, a Wisconsin native, faces brain surgery as the result of injuries incurred by police actions in Oakland this week:

Scott Olsen, the Iraq war veteran who suffered serious head injuries after being hit by a projectile fired by police during the Occupy Oakland protests, has woken up and is lucid as he awaits surgery, hospital officials and family members have said.

Olsen, a 24-year-old former US Marine, was struck in the head during anti-Wall Street protests on Tuesday night. He has been upgraded from critical to fair condition.

Olsen "responded with a very large smile" to a visit from his parents, Highland General hospital spokesman Warren Lyons said. "He's able to understand what's going on. He's able to write and hear but has a little difficulty with his speech," Lyons said.

Doctors had not operated on Olsen yet and were waiting to see if swelling in his brain eased, Lyons said.

Olsen's aunt, Kathy Pacconi, told Reuters in an email that her nephew was showing signs of improvement.

Olsen, 24, has become a figurehead of the Occupy Wall Street movement and Oakland organisers have said they will stage a general strike over what a spokeswoman called the "brutal and vicious" treatment of protesters, including the former Marine.

Oakland's police chief, Howard Jordan, has promised a vigorous investigation into the incident which has provoked heavy criticism across the US, sparking solidarity marches in dozens of Occupy camps in the country.