The United States may finally be getting serious about defanging the Muslim Brotherhood.

A new bill making its way through Congress, the Muslim Brotherhood Terrorist Designation Act of 2025, represents a new chapter in America’s complex history with the oldest and most influential Islamist movement.

The bipartisan legislation, led by Texas Sen. Ted Cruz and Florida Reps. Mario Diaz-Balart and Jared Moskowitz, would for the first time designating the global Brotherhood as a terrorist organization, clearing the way for US sanctions.

Founded in Egypt in 1928, the Brotherhood’s member groups operate in virtually all Muslim-majority countries, as well as in the West.

Each branch proclaims the same core worldview of Muslim supremacy, but adapts tactics and goals to the local environment — some at times engaging in democratic politics and legitimate activism, others deploying brutal violence.

Hamas, the official Palestinian branch of the Brotherhood, is a prime example of this pattern: It has participated in elections and seeks to govern, but also has a 40-year history of unspeakable terror.

America has historically struggled to find a coherent posture toward this complex movement.

It has generally regarded the Brotherhood negatively, at least partially returning the visceral hatred the group spews against the United States.

But at times, Washington has seen the group as a tactical ally on the geopolitical chessboard.

During the Cold War, many US analysts believed the Brothers’ opposition to Communist atheism made them a valid alternative to the Middle East’s Soviet-leaning regimes.

In 2011, when the Brotherhood gained power in various countries after the Arab Spring, President Barack Obama looked at that development with favor — sparking anger in longstanding regional allies.

Many American policymakers and State Department aides remain sympathetic to the Brotherhood, and in academia, support for it is all but reflexive.

Yet, despite the whitewashing attempts of its many cheerleaders, the Brothers — as the ideological forefathers of today’s jihadists — maintain a century-long tradition of anti-Western, anti-American, antisemitic and anti-democratic dogma.

Tellingly, several of al Qaeda’s founders were ex-Brotherhood members — who became disillusioned with the group’s only partial embrace of violence.

Moreover, several Brotherhood branches and spin-offs have directly engaged in violence, and like Hamas have long been designated as terror groups by the United States.

America’s challenges with the Brotherhood are not unique. Most European countries actively monitor the group’s activities on their territory.

In 2014, a British government review concluded that “the aspects of Muslim Brotherhood ideology and tactics, in this country and overseas, are contrary to our values, our national interests and our national security.”

Last month, France released a report making a similar assessment, leading President Emanuel Macron to call for stringent measures against the group.

Cruz’s bill differs from those introduced in Congress in the past.

It does not seek to wholly ban the organization, acknowledging, “Not all Muslim Brotherhood branches are currently violent.”

Rather, it seeks to sanction violent Brotherhood branches around the world — and to create a legal framework for a wider designation in the future.

The measure is gaining support in Congress, and even if it does not pass, President Donald Trump may choose to move against the Brotherhood in an executive order.

Either way, the United States should take a closer look and a tougher position toward the Brotherhood, both abroad and at home.

Internationally, the ambiguous positions of the past must be no more. Instead, US policies should aim to diminish Muslim Brotherhood influence.

Domestically, law-enforcement agencies should use existing legal tools to go after the web of US-based Brotherhood spin-offs.

Whether by designation or not, a tough, clever and coherent Muslim Brotherhood policy would represent a break from decades of half-baked positions — and a step forward in undermining one of America’s historical foes.

Lorenzo Vidino is the director of the Program on Extremism at The George Washington University and author of “The Closed Circle: Joining and Leaving the Muslim Brotherhood in the West.”