Donald Trump's appointment of John Bolton as national security advisor is akin to naming a serial arsonist as fire marshal.

I understand that in some quarters the appointment wins applause on grounds the guy at least brings some knowledge to the subject of national security. But in Bolton's case what he primarily brings to the subject is more gasoline -- and an inclination to use it.

On the record, he's a war monger. He has spoken approvingly of a first-strike military attack on North Korea (despite the destruction the North could quickly visit on South Korea and its 30,000-plus U.S. troops). And while we're at it, why not drop some big ones on Iran?

Like Trump himself, Bolton's a big fan of battle, so long as he's not in it. He escaped service during Vietnam as a Yale student and later by enlisting in the National Guard to, as he once inelegantly put it, avoid "dying in a Southeast Asian rice paddy."

Nothing wrong with the National Guard; it's a grand institution. In my day though, it improved one's chances of avoiding active service in Korea during that unpleasantness. It evidently served a similar purpose in the Vietnam Era.

Bolton is a familiar figure in Washington, usually on the ultra-conservative fringe for GOP politics. The capstone of his career, until now, was brief service as United Nations ambassador under President George W. Bush.

He got a lot of notice in that job, not much of it praiseworthy. Nor did he get much favorable notice during his service in secondary jobs in the State Department. If his critics have it right, Bolton brooks no opinions that differ with his own, hardly the personality you'd look for in a diplomat. But then Bolton routinely disparages diplomats.

His tenure in Washington and the UN was marked by confrontation, not just with foreign emissaries but with his own subordinates -- a "kiss up, kick down" sort of guy, some said. Others accused him of twisting American intelligence findings to bolster his hard-right political views. Sound familiar?

He was a big believer in the Iraq war, for example, never doubting the wildly erroneous claim that Saddam Hussein was sitting on a pile of weapons of mass destruction -- a claim that was a weapon of mass deception.

It should be no surprise that Bolton never won Senate confirmation as UN ambassador; even some Senate Republicans couldn't stomach the guy and his obnoxious personality.

He served an interim appointment at the UN, then quit when that term was up and a confirmation vote he couldn't win loomed if he wanted to continue.

For someone whose job involves at least some modicum of coordination, if not actual cooperation, with foreign counterparts, Bolton seems ill-suited for the post of national security advisor. It he has any sort of a guiding principle it seems to be that the best foreign policy requires America to go it alone with as few allies as possible to consult or interests to consider.

It will be fascinating to see how he gets on with Trump whose "I'm always right, you're always wrong" personality closely resembles his own. The early signals are mixed.

They agree Iran could benefit from a good, thorough bombing. And the president probably can bank on Bolton's support if, come May, he decides to torpedo the nuclear deal with Iran struck by Barack Obama. But beyond that the relationship may need some repair.

For example, originally Trump, like Bolton, was for bombing North Korea preemptively; now the president wants to palaver with Kim Jung-un in pursuit of a deal. How's that likely to sit with the belligerent Bolton? Someone's going to need a change of heart.

Likewise, Bolton in the past has seen Russia and Vladimir Putin as spawn of the devil. But Bolton better have a care there. Putin is Trump's new best friend, remember.

The Russian dictator may even hold some embarrassing Trump IOUs or photos resembling French postcards. Never can tell these days. In any case, it looks like Bolton's going to have to swallow hard and tread lightly where Putin and Russia are concerned.

Bolton's severest critics believe that, unrestrained, he poses a grave threat to the security of the country. Could be -- but probably only if he becomes more of a reckless, right-wing influence on Trump than Trump is on him.

Trump and Bolton. . . .where do we get guys like this? More important still, why do we keep them?

John Farmer may be reached at jfarmer@starledger.com. Find NJ.com Opinion on Facebook.