Adopted cat at age one become aggressive when frightened

One case that may help others understanding why gentle, loving bundle of joy cat, can behave so aggressively, even attacking the owner, when seeing anther cat over the windows.
This particular cat was adopted from a shelter at age one.

Becoming agitated over outside stimuli and then becoming aggressive to the other pets or humans in the house is referred to as redirected aggression. This is often a result of anxious, defensive cat that that has had poor experiences in the past in the outside world. It usually is not self-resolving and ca range from mild to dangerously serious. This is an aggression that must be managed for the rest of the cat’s life. In some, but not all cases, medical management may help the severity of symptoms.

Remember that most if not all pets arriving from a shelter are frightened and can be somewhat aggressive at the first few days. Give them their space, they need to be  adjusted to their new home and  new owner, show your love and be patient.  It worth it.