Wikipedia defines smart antennas as follows
Smart antennas (also known as adaptive array antennas, multiple antennas and, recently, MIMO) are antenna arrays with smart signal processing algorithms used to identify spatial signal signature such as the direction of arrival (DOA) of the signal, and use it to calculate beamforming vectors, to track and locate the antenna beam on the mobile/target.
And phased arrays as follows
In antenna theory, a phased array is an array of antennas in which the relative phases of the respective signals feeding the antennas are set in such a way that the effective radiation pattern of the array is reinforced in a desired direction and suppressed in undesired directions.
From these definitions it seems that two terms define similar things. And yet the article on smart antennas do not reference (in the text) phased arrays and vice versa. To contribute to my confusion, there is a book Adaptive Antennas and Phased Arrays for Radar and Communications by Alan J. Fenn, which has two major parts: one on adaptive antennas and one on phased arrays. These parts address different problems: smart antennas for nulling out interference sources and phased arrays to scan an antenna field of view. And again the core structure looks the same to me.
So what exactly is the difference between smart antennas and phased arrays?