Raffi Khatchadourian traveled to France to visit an unfinished reactor intended to produce thermonuclear energy by reaching temperatures “more than ten times as hot as the sun at its blazing core”:

No one knows [the International Thermonuclear Experimental Reactor]’s true cost, which may be incalculable, but estimates have been rising steadily, and a conservative figure rests at twenty billion dollars—a sum that makes ITER the most expensive scientific instrument on Earth. But if it is truly possible to bottle up a star, and to do so economically, the technology could solve the world’s energy problems for the next thirty million years, and help save the planet from environmental catastrophe. Hydrogen, a primordial element, is the most abundant atom in the universe, a potential fuel that poses little risk of scarcity. Eventually, physicists hope, commercial reactors modelled on ITER will be built, too—generating terawatts of power with no carbon, virtually no pollution, and scant radioactive waste. The reactor would run on no more than seawater and lithium. It would never melt down. It would realize a yearning, as old as the story of Prometheus, to bring the light of the heavens to Earth, and bend it to humanity’s will. ITER, in Latin, means “the way.”

But the reactor hit its latest snag this summer, after repeated delays:

In the previous year, ITER had met barely half its goals. The latest target date for turning on the machine—2020—was again slipping. Officials were now quietly talking about 2023 or 2024. What if the schedule continued to slide? Engineers operate in a world of strictly measured loads and heat fluxes, but political forces are impervious to precise measurement. Still, the ultimate repercussions were obvious: there would come a point, eventually, when frustrated politicians decided that ITER was simply not worth the increasing expense of delay.

In June, the ITER Council gathered in Tokyo, and it was evident that the organization was grappling with its own inner turbulence. At one point, the council member from Korea picked up his papers and stormed out. Ned Sauthoff, the U.S. project manager, bluntly made it known that he thought the project’s nuclear-safety culture was lacking. America’s involvement was growing more tenuous. The Department of Energy had cut funding for a tokamak at M.I.T. to help pay for ITER, and the decision had familiar implications; members of Congress were invited to view the inert machine, and they returned to the Hill expressing outrage. (“ITER is going to eat our whole domestic program.”) Official estimates of the U.S. contribution had doubled, to a billion dollars, and then rose again, to $2.4 billion, merely to get to “first plasma”—essentially, just turning on the machine. Before summer’s end, Dianne Feinstein, the chairwoman of the Senate subcommittee that handles appropriations for energy development, announced that she would discontinue all funding for ITER until the Department of Energy provided a detailed assessment of the total American financial commitment. The request was both logical and impossible to answer accurately; even people at ITER did not know. The department was reluctant to provide a number, and [Ned] Sauthoff told me, “We are in unknown territory.”

Update from a reader:

A somewhat more hopeful example of the pursuit of fusion is the National Ignition Facility here in the States. As I understand it – and I am only an observer from the wings – the Dep’t of Energy largely threw its chips in with this plan for producing and capturing fusion energy, which involves compressing supercooled hydrogen with powerful lasers, rather than superheating it with huge electrical jolts, to create Sun-like conditions. There was big news from the NIF earlier this month: the first energy-positive firings, where more energy came out than went in. Not an end by any means, but a start. A really solid and sober report on NIF is here.

Also too, the thing looks badass.

Update from a reader:

As a physicist working on magnetically confined fusion (but not working on the Iter project), I think the piece gives an unfair view of the project. The US involvement in it has been nothing but trouble: when the Iter project was first considered to be built in the end of ’90s, with major US involvement, it was brought to a halt when US suddenly withdrew support. It took more than 10 years to reconsolidate funding, with additional reductions in design specifications and budget (the original design was decidedly badass, as a sure-fire approach). Currently the US has a 9% stake in the project (like India, Russia, Korea, China and Japan), while the EU funds 45% of it. EU and Japan have an additional bilateral agreement on additional funding for supporting projects such as the IFMIF project. So, the US involvement currently is at best marginal. Is this the best we can do?

While any approach to fusion research is important, I think your reader’s evaluation of the NIF project is lacking. The energy produced in this instance is compared to the energy delivered to the fusion fuel pellet, not total energy used to power the machine. The lasers are about 8% efficient, can be fired about three times per day (when they can), and are used for indirect drive by producing a plasma around the pellet. This means that the energy delivered to the fuel pellet is a tiny fraction of the total, so as a power plant it’s a bust. It does give great insights on what’s happening in a thermonuclear explosion, and appropriately about 5% of the research is highly classified. Not really a fair comparison.

If the Iter fails due to politics and bureaucracy, fusion will be set back probably at least several decades. While it has a lot of detractors, the tokamak is basically the only device so far that has come near engineering break-even, and Iter is projected to produce about 10 times as much as it takes in. Some of the criticism is valid, but it’s still our best shot. Let’s not ruin it.