With their tax votes, the two Arizona ‘mavericks’ chose fiscal irresponsibility and party over country.

As miscalculations go, John McCain’s lighthearted but misguided bid to reach a milestone in Twitter followers was appropriately, in the social media universe, an inconsequential fail.

The Arizona senator sought 74 more followers to hit 3 million; instead, thousands took to an #UnfollowMcCain campaign within hours.

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More long-lasting and serious is the outcry over his vote — and that of fellow Arizona Sen. Jeff Flake — in favor of the GOP tax reform bill that won passage without a single Democratic vote. 

In so doing, McCain and Flake squandered a perfectly good opportunity to cement their legacy as deficit hawks, fiscal conservatives and sensible Republican senators. 

The #UnfollowMcCain campaign matters because it reflected the frustration and anger of Democrats and independents who counted on the “maverick” McCain to reject the tax reform bill that nonpartisan experts say will benefit the wealthiest Americans while hurting the poor and the middle class.

They were holding out for the same maverick who just earlier this year cast the decisive vote that killed legislation to repeal Obamacare.

Flake caved for THAT?

Flake, meanwhile, has been a prominent Trump critic who essentially, and famously, chose to end his political career rather than compromise his “principles” to do what was necessary to win over Trump supporters.

In the tax vote, however, Flake and McCain clearly chose the interest of the Republican Party rather than what’s best for the country. If the senators were going to support the tax bill despite its fiscal irresponsibility, I wish they’d have fought harder to win more consequential concessions.

Flake’s explanation is most baffling because he prides himself as a deficit hawk, yet was nonetheless willing to vote for the plan that could increase the federal deficit by more than $1.4 trillion over a decade.

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And what did Arizonans get in return?…