[terminous]

On its own, "from the river to the sea" is just a description of a geographic area. It is equivalent to a bounded GIS grid. It is not a complete sentence. There is no verb.

I wish for a future where there is peace and love, with no violence, from the river to the sea. I wish for a future where all people, from the river to the sea, have full human rights under the UN Universal Declaration of Human Rights. I wish for a future where all people, from the river to the sea, are enthusiastic users of GNU/Linux and the worst conflicts are debates over text editors.

If someone uses "from the river to the sea" in a sentence where they call for genocide, then what would make that sentence wrong is the verb phrase calling for genocide.