Modern financial and secondary sanctions are the financial equivalent of papal excommunication during medieval times. We now have a really viable alternative to war in our sanctions policies.

The global unity of the financial system has spawned an instrument more effective than bombs and guns: financial exile from the global banking and trade systems.

Since most regimes that we oppose and want to topple — from Iran to Venezuela to North Korea — are, at some level, criminal, the imposition of sanctions blocks these countries and their dictators, personally, from making money which is, in many cases, their ultimate goal. Just as the church says that the spread of religion globally creates one body, so the spread of the financial and banking systems has also created a financial corpus from which exclusion is particularly painful.

As we see North Korea hurrying back to the conference table, Venezuela teetering on the edge of collapse, and Iran putting up with the indignities Trump heaps upon them to salvage the nuclear deal, we can really appreciate the severity and gravity of these sanctions.

Trump has refined a tool for global peace and freedom that may well prove more important than any military buildup.

And, even as Europeans are pushing appeasement, the Trump Administration is stiffening its demands on Iran.

Secretary of State Mike Pompeo, citing Iran’s continued efforts to build nuclear heavy water reactors (that can lead to plutonium nuclear weapons), demands that it close its nuclear reactors. “Iran must stop enrichment and never pursue plutonium reprocessing,” Pompeo said. “This includes closing its heavy water reactor.”

In fact, word is now emerging that President Obama actually secretly used taxpayer dollars to purchase heavy water from Iran to keep its supplies below the levels allowed in the treaty.

The impact of the Iranian sanctions on Europe is particularly dramatic. Even though Paris, London, and Berlin do not want to back out of the nuclear deal, their major companies and multi-national corporations are being forced, by economic reality, to go along with the renewed U.S. sanctions. The secondary sanctions — that block companies from doing business with Iran from conducting commercial relations with companies or people in the U.S. — are forcing them to go along with Washington, albeit kicking and screaming.

In the years after World War II, many Americans assumed that we could lower defense spending and keep power and peace under the nuclear umbrella. President Eisenhower, in particular, embraced this view. President Kennedy disabused America of this notion as the Russian nuclear capability grew to equal ours.

But now, the dominant power of the United States and the interdependence of global finance have created a new era where financial and diplomatic power may become predominant. When the “soft” power in which Europeans say they believe, is combined with effective sanctions — and the willingness to maintain them — it can sweep all before it.

Dick Morris is a former adviser to President Bill Clinton as well as a political author, pollster, and consultant. His most recent book, “Rogue Spooks,” was written with his wife, Eileen McGann.