The global resurgence of anti-Semitism that we are experiencing today began almost 20 year ago, mainly in Europe. At the time, I was serving as Israel's Minister for Diaspora Affairs and was grappling with the question of how to distinguish between legitimate criticism of Israel and anti-Semitism.

That is when I came up with what I call "the 3D test for anti-Semitism"—the three Ds are demonization, delegitimization and double standards.

If we watch a 3D movie without 3D glasses, we see a blurred, partial picture. But when we put on our 3D glasses everything becomes clear—and when we use the 3D test for anti-Semitism we can easily distinguish between legitimate criticism and anti-Semitism.

These 3Ds—demonization, delegitimization and double standards—are the three main tools that anti-Semites employed against Jews throughout history. For thousands of years, Jews were demonized, they were charged with blood libels, with poisoning wells, and, later, with controlling the global banking system. The Jewish faith and the Jewish claim to nationhood was delegitimized. And double standards were applied to Jews, either through the imposition of special laws—from the Middle Ages in Europe, to the Russian Empire and Nazi Germany— or through de -facto government policy discriminating against Jews, as I experienced in the Soviet Union.

Throughout history, demonization of Jewish people, delegitimization of their faith or nationhood, and double standards applied to Jews created fertile soil for pogroms, expulsions and genocide.

My 3D test shows that if we see these same tools of delegitimization, demonization and double standards that were used against Jews in the past being used against the collective Jew, the Jewish State, today—we know we are witnessing a new face of the old anti-Semitism.

Many who support the Boycott, Divestment, Sanctions (BDS) movement may do so out of a naive belief that it is working to achieve a solution to the Israeli-Palestinian conflict. While there is a network of civil society organizations that promote boycott of Israel, the movement takes it cue by the BDS National Committee, established in 2005 and based in Ramallah, in the West Bank.

It has but one goal: the destruction of the State of Israel. This goal is cleverly masked behind the veneer of fighting for human rights and legitimate criticism of Israel. When caricatures against Israeli leaders repeat the worst anti-Semitic caricatures of Czarist Russia or Nazi Germany, and this time it is Israelis who are crucifying Palestinians or making ritual use of their blood, and when Palestinians are portrayed as living in Nazi death camps—that is demonization; that is the blood libel of today; that is anti-Semitism. You can find over 80 examples of such tropes being disseminated or tolerated by prominent figures in the BDS movement in the report we released earlier today.

When the legitimacy of the Jewish State is denied and, in the language of some of the founders and key promoters of BDS, there is no place for a Jewish state in the Middle East in any borders – that is delegitimization; that is anti-Semitism. The true aim of many of the movement's key figures has been the destruction of Israel as we know it. Indeed, the movement's co-founder and leader Omar Barghouti has said so, unequivocally: "Definitely, most definitely we oppose a Jewish state in any part of Palestine.''

And when the Jewish State is singled out for criticism that not even the vilest dictatorship is subject to and it is held to standards that not even the most vibrant democracy is judged by—those are double standards; and that is anti-Semitism.

There is always place for criticism of Israel, as there is for criticism of any other free society. But it must not cross the line of anti-Semitism. When people talk about Israel, we have to identify whether these three elements of delegitimization, demonization and double standards apply to judge whether that criticism is tainted with anti-Semitism.

This week Israel's Ministry of Strategic Affairs released a report that provides great detail on the links between BDS and anti-Semitism. The report cites over 80 examples of leading BDS activists and organizations making statements or promoting content that is anti-Semitic.

Just as the anti-Semites of yesteryear sought to prepare the ground for the expulsion and murder of Jews, leaders and key figures in the BDS movement seek to use the ancient tools of demonization, delegitimization and double standards to put in place the foundations for a world without Israel. The movement seeks to bring the level of hatred against Israel today to the level of hatred against Jews in the past, to delegitimize the Jewish state to the point where it is seen by the world as a cancer that should be removed. It is the same approach that created the atmosphere that can lead to bloodshed.

We all have to work together to improve the world. Those who want a better world shouldn't give a hand to those whose aim is to see a world without Israel.

Natan Sharanksy is a former Prisoner of Zion. He was Israel's Minister for Diaspora Affairs and Deputy Prime Minister. He served as Chairman of the Jewish Agency for Israel and was recently named as Chair of The Institute for the Study of Global Anti-Semitism and Policy.

The views expressed in this article are the author's own.