"Through these Nordic layers of foreignness we can see that Ender was not a true xenocide, for when he destroyed the buggers, we knew them only as varelse; it was not until years later, when the original Speaker for the Dead wrote the Hive Queen and the Hegemon, that humankind first understood that the buggers were not varelse at all, but ramen; until that time there had been no understanding between bugger and human." (2.24)
The claim here is that if you don't see your enemy as human, then you're not really committing genocide against them. But in fact, humans usually decide that the enemy is not human as a prelude to, or as an excuse for, killing them. The buggers had spaceships and advanced technology; Ender and everybody else knew they were intelligent, and they certainly knew they weren't animals. The way the argument is phrased, you could let the Nazis off the hook because they thought Jewish people were subhuman monsters, and how were they to know killing them was a bad idea?
Their only intercourse with other tribes seems to be warfare. When they tell stories to each other (usually during rainy weather), it almost always deals with battles and heroes. (6.1)
Interestingly, we never see the piggies go to war in the novel, though they're supposed to be extremely warlike. The only violence we see them commit is the killing of Pipo and Libo, which is kind of a mistake. Would we like the piggies less if we saw them at war?
"He wrote cruelly, to turn their pride to regret, their joy to grief. And now human beings have completely forgotten that once they hated the buggers, that once they honored and celebrated a name that is now unspeakable—" (8.47)
We see Ender as the bullied underdog sent to war in Ender's Game; then in Speaker for the Dead, we see him as the hated xenocide. Despite his great capacity for violence and his massive war crime, Ender is always the despised underdog. This seems maybe problematic.
Someday, Libo warned them, there may be trouble between human and piggy; we will make no path to guide a pogrom to its destination. (9.77)
Libo is very reasonably worried about war between human and piggies. He's trying to thwart human attacks on piggies, which someone could probably see as a kind of treason. As the novel notes in many different contexts, trying for peace in wartime tends to get you seen as an enemy.
"We are dead!" shouted Human. Miro had never seen him so agitated. "We are being murdered every day. Humans are filling up all the worlds. The human build their stupid fence to keep us out, but that is nothing. The sky is our fence!" (14.195)
Human basically equates the restrictions on the piggies with war; not being able to expand is seen as cultural death. If there is to be peace and equality there must be… Piggies in Space.
"The chance for what?"
"To undo what Ender did in the Xenocide three thousand years ago." (15.202-203)
The hope is that peace with the piggies will undo the destruction of the buggers. This is especially the case because the buggers will also establish themselves on the piggies's world. Still, while peace can end or heal war, does it undo the past? Ender killed lots of folks, and while learning peace from that is a good thing, it doesn't bring the dead back to life.
Is this what all their work and sacrifice was for, to give some transient advantage for one tribe of piggies? Almost he said, Libo didn't die so you could conquer the world. (16.146)
The xenologist's efforts to help the piggies is quite possibly going to result in war and death. Good intentions, road to hell, etc. (Though of course the road does not lead to hell after all, because Speaker for the Dead is determined that good intentions are good, so we don't ever really see good intentions go awry.)
"Cutting off the ansible, or even seeming to, would be an act of rebellion. Of war." Bosquinha was saying it as harshly as possible, but Ender could see that the idea appealed to her. (16.228)
War is here equated with an end to communication, and refusal to communicate in the novel is seen as an aggressive act. Remember that Ender turning off Jane and not communicating with her is seen as really bad. In the world of Speaker for the Dead, you better answer your smartphone, no matter who's calling.
Everybody condemns the Xenocide because it destroyed an alien species that turned out to be harmless in its intentions. But as long as it seemed that the buggers were determined to destroy humankind, the leader of humanity had no choice but to fight back with all their strength. We are presenting them with the same dilemma again. (16.311)
Is it Shmoop, or is this passage justifying the xenocide? It seems especially odd because Speaker actually works to show that you do have other options when attacked—as the piggies point out, the humans didn't kill all the piggies when Pipo was tortured to death. Peace and patience are options. Maybe the book just gets confused because it's so eager to defend Ender?
"To grow until all the space you can see is part of you, under your control. It's the desire for greatness. There are two ways, though, to fulfill it. One way is to kill anything that is not yourself, to swallow it up or destroy it, until nothing is left to oppose you. But that way is evil." (17.300)
War is seen as the perverted form of a natural desire for expansion and survival. Ender argues that you could instead expand through alliances, or through joining with other people. Would it be possible just not to want to expand, to just want to hunker down and mind your own business? Shmoop thinks so—though maybe that's just because Shmoop is the retiring type.