It was a devastating loss for the Washington establishment: Former state Supreme Court justice Roy Moore decisively defeated Sen. Luther Strange in Alabama's  Republican Senate primary runoff. 

The outcome was never in doubt, and the message Tuesday was even clearer: We want Washington to deliver on President Trump's platform.

Roy Moore, left, and Sen. Luther Strange will face off in Alabama's GOP primary runoff on Sept. 26, 2017.

Months after voting for Trump’s promising agenda, the American people are sick and tired of the do-nothing Congress, which has consistently failed to deliver results for people in need of common-sense conservative reforms and long overdue economic growth. This comes as no surprise to those of us involved in the Trump movement from the beginning — we spotted voters’ anti-establishment sentiment last year.

Strange was the living embodiment of a legislature that had failed to repeal and replace the Obamacare disaster, while also wavering on tax cuts and showing little commitment to building the wall. Conservatives like Sarah Palin — who headlined a rally of ours last week — said enough was enough in Alabama. 

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The week leading up to Tuesday encapsulates the establishment’s outdated brand of politics. Strange flooded Alabama’s airwaves with nasty, fallacy-filled attack advertisements targeting Moore’s personal reputation. Rather than touting Strange’s record, the ads desperately vilified a proven conservative with misleading statistics and cherry-picked quotes.

It seems the establishment class is more interested in protecting their incumbency than working with the president on his agenda, which 63 million voters supported last November. Ironically, if establishment Republicans would only listen to Americans outside the Beltway, they would be able to help grow the Republican Party and pass much-needed conservative reforms.

With or without their help, change will still happen — in Alabama and beyond. In Arizona, former state Sen. Kelli Ward is challenging Republican Sen. Jeff Flake, who has consistently turned his back on Republican voters by publicly criticizing Trump and opposing the border wall to combat illegal immigration. Early polls show Ward with a double-digit lead, in part because of Flake’s weak immigration stance. The Grand Canyon State is home to over 300,000 illegal immigrants, making Flake’s establishment bona fides all the more untenable. 

Moreover, Sean Hannity and Laura Ingraham have already endorsed Ward’s strong immigration credentials, furthering the divide between establishment Republicans and grassroots conservatives. In Hannity’s words: “I cannot any longer support weak Republicans. I will not support people who break their promises.”

Many Arizonans rightly agree. Flake has not only flip-flopped on border security, but also on gun control, much to the chagrin of Arizona’s Second Amendment supporters.

More importantly, Flake has made it a mission to publicly undercut the president and the very people who voted for him. In 2016, the Arizona senator called on Trump to drop out of the race. More recently, he claimed Trump is “inviting” a 2020 primary challenge by “drilling down on the base.” 

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Aren’t political leaders supposed to listen to their supporters? Flake’s words imply the president should not follow through on his campaign promises — a stunning admission for any elected official.

There is nothing more infuriating to Americans seeking change than two-faced politicians, who give conservative stump speeches only to govern as centrists. Contrary to the mainstream media’s best wishes, Trump voters are not growing tired of the administration; they are growing frustrated that the “America First” agenda they supported is stuck in the swamp because of never-Trumpers like Flake.

This growing frustration makes the path forward straightforward for outsiders. Speak to your base. Mobilize conservative activists. Enlist the help of outside groups to build enduring grassroots coalitions. Motivate voters to vote on Election Day. When you are elected, stay true to your word.

Establishment, beware: We’re coming for you in 2018.

Eric Beach is co-chairman of the Great America Alliance, an advocacy group that supports President Trump’s agenda. Follow him on Twitter: @ericbeachgop

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