What world is John talking about? He is talking about the people on earth who are Carnal Minded having never received the Gospel of Jesus Christ.
Those who are Carnal Minded cannot understand those who have become Spiritual Minded by receiving the Truth and being Born Again.
We can't love by command because it would not be genuine. We love naturally by virtue of the Holy Spirit in us.
The manifestation of Holy Spirit Love in us is evidence that we are In Christ Jesus, the perfect manifestation of Holy Spirit Love.
We love as Jesus loves by His Holy Spirit.