It's been policy hereabout to ignore presidential tweets of no national consequence.

Whether President Donald Trump likes Roseanne or dislikes Rosie matters not. But Trump's tweets about the catastrophic California fires do. They demonstrated remarkable ignorance and cowardice. And in the words that weren't there, they showed a collapse of the leadership needed to defend this country from the onrushing disaster of climate change.

"Bad environmental laws," he tweeted, have diverted needed water "into the Pacific Ocean," making the wildfires "so much worse." That's the ignorance part.

The claim that firefighters don't have enough water is not true, and to a moronic degree. "We're having no problems as far as access to water supply," said Scott McClean, deputy chief of the California Department of Forestry and Fire Protection.

Rob Stutzman, a prominent Republican strategist in California, called that tweet "nuts," as well as "frightening" in its dumbness. Water plays a surprisingly small part in fighting wildfires. The main weapons are flame-retarding chemicals dropped from planes and creating physical fire breaks.

The tweet may also reflect crossed mental wires confusing the wildfire crisis with the ongoing disputes over dividing available water between farms and fish. (As for the fish, it's not just the Delta smelt. Salmon farming is a huge business.) The connection seems to have flown directly out of the presidential belfry.

The cowardice comes from using the calamity to insert unrelated and unpopular policy goals. "Must also tree clear to stop fire from spreading!" Trump tweeted. Back story: Trump wants to let timber companies resume logging in California's Los Padres National Forest. There is a solid "fire" argument for removing dry underbrush, but not for chopping down healthy green pines.

The "bad" environmental policies that Trump tweets about are his own -- or rather, his lack thereof when it comes to combatting global warming.

Scientists blame rising temperatures for the intensity of recent fires and flooding, threats that could make large chunks of the United States uninhabitable. The tweets make no mention of climate change. As a political matter, the extreme heat is currently burning up blue states and red states alike. And Trump is doing everything in his power to escape responsibility.

California has become a world player in moving its economy off the fossil fuels that contribute to warming. That others are following its lead clearly fries the president. He's now working hard to overthrow California's fuel economy rules for vehicles, a standard followed by many other states.

Trump holds that battling climate change is bad for the U.S. economy. It happens that California is doing it and its economy is a lot better than Trump's. Gov. Jerry Brown will soon be leaving office with a budget surplus of $9 billion this fiscal year. By contrast, Trump's tax cuts and spending will explode the federal deficit to $1 trillion by 2019. (By the way, the deficit had fallen to $587 billion under Barack Obama.)

Did we neglect to mention that California will have also built up a $16 billion cushion of reserves by next year? That will come in handy for the coming recession.

When the president specifically blamed Brown for the nonexistent lack of water for firefighting, an exasperated Stutzman urged the governor to "not take the bait" by responding. And indeed, Brown did not, preferring to scold the media for spending so much time on Trump's verbal spasms.

"It's a sad state of affairs when journalism is reduced to chasing the uninformed, unsupervised tweets of the president," Brown's spokesman told Politico.

He's not wrong about that, generally. But unsupervised and dangerously ignorant tweets from someone who still is president do require attention. A dereliction of national duty cannot be brushed off.

Froma Harrop (fharrop@gmail.com) writes for Creators Syndicate.