He is God's mission to a fallen world, not a fallen world's mission to domesticate God. He enters Jerusalem in order to penetrate to the very heart of a religion gone selfish and sour. The praise and acclaim of the crowds along the way mean nothing to him except that his well-wishers haven't the vaguest notion of who he is or what he is seeking to accomplish. His identity is one with his Father in heaven. And his marching orders come from God, not from the world.
Popularity is deceptive, especially for the church.
We do well to heed the message of Palm Sunday in which we see how easily the crowds in ancient days and even the crowds today are misled into cheering what they want to see in Jesus Christ rather than honoring him for who he actually is. Jesus had enemies. So does the church. But when the church comes to the point of believing that it has no enemies at all, then either the church is better than its Lord or else it has replaced its Lord with a lesser god better suited to itself. Just as wise parents know that they are under assignment from God to do what is best for their child, which may or may not always be what their child actually wants at that moment, so also the church knows that it is always under assignment from God to do what is best for the world, whether that is what the world actually wants or not.