Is it true to say that because “God is love” (1 John), we can say “Love is God”?
From a strictly logical perspective, it is not always the case that if A is B, then B is A. However, is the nature of God such that it is true to say that love is God? In other words, does St. John mean to say that God=love? I don’t know Greek. Maybe that is what he said.
No it is not true that one can reverse the order.
However just because we cannot reverse the order does not mean that the significance of the statement “God is love” is lessened any.
I can say Joe is human but I cannot say Human is Joe correct? (unless I’m Yoda…

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Yet - When I say that Joe is Human - I am defining something very elemental AND complete about Joe. He is fully and completely human. AND being human, in many respects, defines who James is.
“God is Love” in a way - is the same thing. Even though God is other things, Love is a very defining characteristic of who/what He is. He is fully Love.
But going beyond that God is the embodiment and the source of Love. Seeking after Love (Agape) is very much the same as seeking after God Himself. John makes that apparent in the letter you reference:
1John 4:7-8
7 Beloved, let us love one another; for love is of God, and he who loves is born of God and knows God. 8 He who does not love does not know God; for God is love.
That said, it is very important not to conflate the two things for as someone already mentioned, in our modern terminology there are many different meanings for the word Love. So when we go looking for the Love that God is, we must learn what comprises that love so we get it right and are truly pursuing god and not some other flesh or spirit…
Peace
James