Luke was hesitant to go, simply because he knew he and Jacen still did not agree on so much. He cared about the younger man, a lot, and wished he could find a way to convince the other of what he knew to be true. However, today was not about that, not for Luke.
Today was about finding something that had been lost. Today was about giving a little, too, and hoping that, between them, they could forge a peace. That, and getting close enough to truly sense Jacen's disposition in the Force. Their discussion had disturbed him and he was not sure where his nephew sat in things now.
Either way, today, Luke walked with no saber and no blaster when he walked into the cafe. Not that he would need one even in the worst case, but the symbolism was necessary. He was not there to make war. He had come to tell Jacen one thing, one important thing. Luke still loved the man he had once taught personally. He still cared for this man, and he hoped, someday, they could find like cause again.
He stepped into the cafe, his presence quiet, if not shielded in the Force, one emotion forthmost; hope.