Actually, this is how it went down.
You told me that a war between Italy and Germany was something you were willing to risk, when you intimidated Austria, and I warned you that if you did you might have ended up in a war with Italy. I told you that it would be a real war in that case. So I went out to look for allies should such a war happen, if it did not conflict with my victory conditions. Not being able to achieve my mandatory victory condition (taking Malta), I negotiated to get it. So once that happened, the treaty was signed. I did not need to take my mandatory victory condition, by force.
The rest of my victory conditions are of course secret, but not all of them require war with the allies, nor Germany.
What Japan is up to I have no idea.