Both sides used politicians to defend their causes. Both Zwingli and Calvin exercised political power. Luther would not have survived except it was expedient for his sovereign—the Elector—to protect him. Germany divided into pro-and anti-Luther in order to keep the Emperor Charles from uniting the country under his rule. Religious questions were confused with political causes and with the Religious Wars in France, a century of slaughter began, to the final disgrace of both parties.
Agreed. Above and beyond the Protestant states with their state religion, there were those within Roman Catholicism, which did the same.
The novelty of deliberately detaching the power of the state from matters of conscience regarding religious belief is largely taken for granted now, but it was genius born of hardship and persecution experienced by the people, both here in colonial times and in the various nations of their origin.
So, it can be said that some good came of it, ugly as it was.