Story highlights Errol Louis: The health care flub shows why the GOP shouldn't shut out Democrats

It also shows the folly of putting their agenda at the mercy of GOP extremists, he says

Errol Louis is the host of "Inside City Hall," a nightly political show on NY1, a New York all-news channel. The opinions expressed in this commentary are solely those of the author.

(CNN) This was far more than a routine legislative flub. It is a warning to congressional Republicans and the Trump White House.

The embarrassing collapse of the Republican effort to repeal and replace the Affordable Care Act makes clear the limits of the GOP's unwise, unworkable insistence on shutting Democrats out of lawmaking. The refusal to move any piece of legislation forward without Democratic votes will bedevil Ryan and Trump as they attempt to rewrite the tax codes, immigration laws and the nation's multi-trillion-dollar budget.

For decades, success in Congress depended on an alliance between Republicans and conservative, so-called Blue Dog Democrats. The result was a string of centrist deals that marginalized ultra-liberal and super conservative members and allowed legislation to move forward.

That system broke down in the 1990s. Election after election, conservative Democrats got wiped out in the South, while liberal Republicans were rendered extinct in New England and other Northeastern districts.

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But having more conservatives in the GOP conference doesn't always help the party get things done. By making every vote a matter of securing a near-unanimous Republican majority -- and by shunning any possibility of working with conservative Democrats on select issues -- Ryan, like his predecessor, John Boehner, has placed himself in thrall to the most hard-line conservatives in his conference, the so-called Freedom Caucus.

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