Alignment is working towards a shared goal. How the goal will be achieved is accepted by all parties, but each individual may have different reasons for getting there. Alignment can be temporary or permanent, transactional or self-less, value-driven or amoral.
Unity is different. Unity is a commitment to shared values, regardless of any particular alignment. You can be unified and disagree forcefully. That happens in all healthy marriages, workplaces, and countries.
Unity asks: What am I willing to give up to make this relationship work? What matters most to us? What is bigger than me?
Unity isn’t fundamentally moral, but it works best when it embraces noble values. So regardless of what else we believe, it’s worthwhile to be unified around kindness, honesty, accountability, sacrifice, justice, apology, and compassion.