The phrase "paper tiger" means something or someone that appears powerful and threatening, but is actually weak and lacks true strength or substance. Full definition
Although strong tonic for the local fans, the flurries of touchdowns, the long runs and the passing averages that read like election returns are usually made against opposition as fierce as paper tigers. (si.com)
I'm quick to mix my metaphors and now have in mind an image of a fence of paper tigers protecting a falling tree at the top of a cliff, with a horse drawn ambulance at the bottom. (slaw.ca)
Dr. Esselsyn (pictured, right, also happens to be Engine 2 Diet author Rip Esselstyn's dad) starts by saying, «If the truth were known, that coronary artery disease is a toothless paper tiger that need never exist. (mindbodygreen.com)