I got an email not too long ago from the head of a conservative faction of the Kauai Republican Party, who declared, “We are waging war against the forces of evil.”

I shook my head, discouraged our political discourse has sunk so low that Republicans and Democrats talk about each other like this.

Then I read on and discovered the “evil” he railed about wasn’t Democrats, but fellow Republicans of differing views.

Such is the sad state of today’s Hawaii GOP, mired in irrelevance as members bash, sue and purge each other; issue apocalyptic ideological threats; and spread tabloidlike gossip of marital infidelity among adversaries.

Against this backdrop, I read with sorrow that state Rep. Cynthia Thielen, Hawaii’s last elected Republican with any semblance of broad credibility, will retire next year from the Kailua House seat she’s held for 30 years.

Thielen, 86, calls herself “The last Eisenhower Republican,” citing this quote from the late President Dwight D. Eisenhower: “In all those things which deal with people, be liberal, be human. In all those things which deal with people’s money, or their economy, or their form of government, be conservative.”

She’s lived up to that ideal in the Legislature, acting with class befitting her office while fiercely advocating for her priorities.

Thielen often gives Democrats sharp common-sense spankings when it comes to minding the public pocketbook, but works willingly across the aisle on issues like the environment, which she considers an existential concern in an island state.

She gave then-Democratic lawmakers Kirk Caldwell and Blake Oshiro a memorable upbraiding in 2008 when they argued that homelessness wasn’t an emergency.

“That’s the most heartless comment I’ve ever heard in this chamber,” Thielen scolded. “Go out there and be with them and see what it’s like and tell me that’s not an emergency in those people’s lives.”

She drew the ire of the GOP right for supporting gay marriage, but easily survived their primary challenge in a district she knew intimately from walking it every two years whether she had an opponent or not.

Thielen is an old-school legislator who still communicates by writing letters.

She’s the last of a long line of tough, practical-minded Republican legislators like Pat Saiki, Andy Anderson, Richard Henderson and Mary George, who operated effectively in a Democratic state by arguing their points forcefully but without personal rancor.

Thielen stuck with the GOP and tried to rekindle a two-party state as others such as Anderson, Charles Djou, Kymberly Pine and Beth Fukumoto left the party over the ugly infighting and ideological wars.

It’s been a long time since the Hawaii Republican Party was a force to be taken seriously, and it will be less so with Cynthia Thielen’s departure from the Legislature.

Reach David Shapiro at volcanicash@gmail.com.