While there is always international collaboration necessary to construct and run a particle collider, it is a lost opportunity for U.S. science, which was able to attract high energy physicists from all over the world until the Tevatron was shut down in 2011.
Nature quoted Barry Barish, the head of the global design effort for the ILC, stating: "Japan is it." Barish and his team already provided the design blueprint of the 31 km (19.3 miles) long collider to an independent committee of researchers. In contrast to the LHC, the ILC is designed to collide protons and anti-protons, whereas the LHC only uses protons. The entire structure that is currently planned to reach an energy level of 1 TeV.
A small version of the ILC called Superconducting RF (SRF) test facility has been constructed at Fermilab for about $60 million. However, the ILC was originally planned to cost about $4 billion, and is now estimated to cost well over $10 billion.