In a Taiwan war, the US could find itself fighting China without its top allies

• The US military may be forced to confront a Chinese invasion of Taiwan without top allies.
• Japan, Australia, the UK and Canada are likely to provide no military forces to counter China.
• RAND Corp. analysts said these "middle powers" could help in other ways, however.

If the US decides to defend Taiwan from Chinese invasion, it may have to do so alone.

Several of America's biggest allies are unlikely to commit troops to save Taiwan, either because they lack the military capability or don't want to risk all-out war with an increasingly formidable China, according to a new report by the RAND Corp..