The United States must make a bid to host the International Linear Collider (ILC), according to a report out this week from the National Academy of Sciences. If the multi-billion-dollar particle accelerator is not built on US soil, the nation's high-energy physics community may be doomed.

High-energy physicists globally have endorsed the ILC as the next big project for the field. The collider, 30 kilometres in length, would smash together electrons and their anti-particles, known as positrons, at 500 GeV in the hope of probing fundamental particles, including the yet-to-be-discovered Higgs particle.

Without a serious bid, the community is going to atrophy.

“Without a serious bid, the community is going to atrophy,” warns Harold Shapiro, an economist from Princeton University who chaired the panel that produced the report; the panel was convened by the US Department of Energy and the National Science Foundation, which together fund the lion's share of high-energy physics research in the United States. In addition to recommending that the government make a strong bid for the project, the panel suggests that it invests in high-energy astrophysics and neutrino research. There are currently around 2,000 high-energy physicists working in the United States.

The report comes at a precarious time for high-energy physics in America. Earlier this year, budget cutbacks forced the Relativistic Heavy Ion Collider to take a private donation to continue operations, and the Tevatron, the nation's premier accelerator at the Fermi National Accelerator Laboratory, or Fermilab, in Batavia, Illinois, is expected to shut down within three to four years (see Nature 435, 728–729; 2005). “There doesn't seem to be a next step in place,” Shapiro says. “This is a moment where important decisions have to be made.”

Although the report will strengthen scientists' case for the project, Mike Lubell, head of public affairs for the American Physical Society in Washington DC, cautions that the collider — estimated to cost at least $6 billion — still faces an uphill battle. “In an era where the government is not keen on raising taxes or cutting defence funding, a big project like this is going to run into a lot of problems,” he says.

“I think this report will be very welcome in Europe,” says Brian Foster, a physicist at the University of Oxford, UK, who is heading the European design effort for the collider. Foster says that the Large Hadron Collider, a $2.5-billion accelerator being built at CERN, the European particle-physics laboratory in Geneva, Switzerland, is consuming most of the continent's resources. A strong US bid for the ILC, he says, will strengthen the prospects of the collider, although he adds that Russia, Japan and China have all expressed interest in hosting it.