Israel’s military says it deployed a rocket defense system to the center of the country amid threats by Gaza militants.
Not that the threat from Gaza isn't a reason.
I'm just saying that if Israel plans to hammer Hezbollah by invading Lebanon before Hezbollah can redeploy troops from Syria, it would be nice to have additional missile and rocket defenses in place without telegraphing the primary intent of the missiles.
So Hamas is a good excuse.