My husband and I did when Zoe was only about a year old. We didn't even think about it- it was a reaction. In the dog park (of course) a lab/pitt mix just went after her for no reason. The woman with him (we found out later she was not his owner) just stood there horrified, not knowing what to do. My husband, wearing heavy boots kicked the dog's butt hard enough to startle him for a moment. In that time I grabbed Zoe. The woman got control of the dog and leashed him. We started to admonish her, then found out he was her husband's dog, and that her husband had passed away pretty recently. She just didn't know he would react that way. Since Zoe wasn't hurt and the woman meant no harm, we just advised her to do some training with him and keep in out of the park.
But in answer to the original question- yes, in a moment and without a second thought.