There wasn't time to make a conscious decision. Harry reacted automatically, as he had been trained to do in the Auror Academy. The one he went to alone, since Ron hadn't been able to pass the entrance exams.
Ron had pouted and whined endlessly as Harry got ready to leave for the Academy. Even Arthur pointed out that Aurors needed a minimal level of skill in many areas to perform their job properly.
Ron showed up at the 'good luck' party to eat the meal Molly had prepared but left immediately. He never spoke to Harry that night.
Harry learned more about magic at the Academy than from even Hermione. How charms were created and why they worked as they did. The real history of magic and how Zir and Fate walked amongst them daily. He learned there were good people, men and women who valued Harry for his hard work and determination.
There were always those that cared about his money and his fame but his new friends protected him. Harry learned what friendship really was. Sharing hopes and dreams, good times and bad. The men and women on his team became the family Harry never had.
Harry's team was assigned to uncover a petty theft ring. The robbers took advantage of easy pickings, using magic against Muggle households.
The Muggle-born witch on his team and her sister talked about valuables at their empty parents' home as they walked Diagon Alley. The family was evacuated and the team set up surveillance.
Two intruders tripped the notification wards. They hadn't prepared for a third person outside the wards. Harry's partner fell to a Stunner. He whirled to face the threat.
The person crumpled and lay silent. Harry strode over to look down at Ron's slack face.