A survey of the big chunks of metal and concrete keeping our tourists and federal workers safe. The Department of State still has giant planters everywhere.That statue at the World Bank could probably also stop a truck. Bollards can double as bike racks! But not very well.Slightly better disguised planter bollards at the Hirshhorn.Decorative chunks of concrete behind the Freer and the Sackler.The Holocaust Museum went with a vaguely art deco theme.The Air and Space museums bollards look like something out of Star Trek. s bollards look like something out of Star Trek. The Hirshhorn is supposed to get permanent bollards soon. The Museum of Natural History: Sort of rust-adorned bollards, like the old things inside.The FBI building, with high-tech planters protecting its closed doors.The Museum of American Historys spiffy new granite plinths. s spiffy new granite plinths. And the Museum of American Historys sleek, simple bollard look. s sleek, simple bollard look. The Department of Health and Human Services took the gumdrop bollard approach. Voice of America, still stuck with jersey barriers.The open plaza at Health and Human Services, with truck bomb-blocking sculptures.