Andrew Gillum won a stunning upset victory in the Democratic primary for the Florida governor's race on Tuesday night. He will face off against Ron DeSantis, an unhinged Trump lickspittle who subtly referred to Gillum (a black man) as a monkey the very next morning. It's anybody's guess who will win — Gillum was down by 14 points in the final primary polls — but it's sure to be a heated, bitter race.

But in other Florida news, Bloomberg Businessweek published a large investigation into the water supply system in the state's second-largest city, Miami. In brief, the situation is dire. It's a good demonstration of the partisan stakes in American politics — because Republicans will let Florida drown.

Gillum — though he is an experienced politician, winning his first race in 2003 — ran largely on the cutting-edge suite of lefty policies, including Medicare-for-all, the overhaul of ICE, and strong climate policy. His issues page attacks President Trump and current Gov. Rick Scott (R) for having "failed to take action against climate change, with Florida having the most property at risk in the nation" and suggests a big investment program to protect the Florida environment and transition quickly to clean energy.

That last priority would be perfectly natural not just for a lefty, but for any Florida resident whose head is not cross-threaded onto his spinal column. As the Bloomberg article lays out, Miami (and by extension the whole southern Florida coast) is facing an existential emergency whose slow-moving nature only makes it more threatening.

The upper range of the Intergovernmental Panel on Climate Change's sea level-rise scenarios would permanently inundate vast swathes of Miami by 2100, and especially its even more exposed neighbor Miami Beach, parts of which already flood every time there is a big "king tide" — and that's leaving aside preliminary studies on the possibility of much greater rise due to a rapid collapse of the ice sheets of Greenland or West Antarctica. Sea levels will continue to rise for hundreds of years after that. What's more, it would be nearly impossible to build seawalls around Miami or any of its neighbors, because it is built on highly porous limestone — absent foundations going down hundreds of feet, the water would just come up out of the ground.

That limestone foundation makes for the most immediate threat: groundwater contamination. Rising seas are gradually pushing salt into the aquifer that the cities tap for drinking water, while associated flooding washes toxic materials from contaminated locations and swamped septic tanks into the aquifer as well. All this is also disrupting the region's incredibly elaborate water management system, worsening both problems:

The permeability that makes the aquifer so easily accessible also makes it vulnerable. "It's very easy to contaminate our aquifer," says Rachel Silverstein, executive director of Miami Waterkeeper, a local environmental protection group. And the consequences could be sweeping. "Drinking water supply is always an existential question." [Bloomberg Businessweek]

Meanwhile, every inch of sea level rise increases the vulnerability to hurricanes — which is already high. Hurricane Andrew inflicted catastrophic damage on South Florida in 1992 mainly with high winds, but if Miami gets dead-centered by a strong hurricane pushing a big storm surge (which is certain to happen sooner or later), it would cause hundreds of billions of dollars in damage at a minimum.

Just to stave off the worst effects of climate change that are already locked in (the huge inertia of the climate system means the effects of today's emissions won't be felt for decades) is unquestionably going to take massive help from the federal government — as it did to make Florida even remotely habitable in the first place.

Moreover, even if Gillum wins and somehow changes the entire state to 100 percent renewable energy overnight, that will only slightly dent America's greenhouse gas emissions — and won't touch world emissions as a whole, which is mainly about China and India at this point. Climate change is an inherently international problem — but a solvable one, because both of those countries will be harmed even worse than the United States if warming spirals out of control and because both countries are already doing something about it.

A national government with even a slight grasp of science and elementary reasoning would conclude the following: Florida (and most other states) needs a crash investment program from the federal government to both transition to zero-emission energy and ruggedize its built environment to withstand climate disasters. Second, the federal government must pursue an international climate bargain as its number one foreign policy priority. For the Miami community, it is quite literally a matter of whether it will be allowed to exist in the future.

President Trump and the Republican Party, naturally, are doing the precise opposite of this, withdrawing from the Paris climate accords and (among other things) doing all they can to maximize not just greenhouse emissions, but seemingly even the number of people who die from respiratory diseases caused by filthy coal power pollution. Ron DeSantis — who has a 2 percent lifetime rating from the League of Conservation Voters — has questioned the reality of climate science and signed on a letter of protest against international climate funding.

If the right has anything to do with it, Florida will drown.