Why would dfx nns install and then dfx nns import not install/import the identity canisters?

```
nns-identity has no local canister ID.
nns-ui has no local canister ID.
nns-sns-wasm canister id on network 'local' is qaa6y-5yaaa-aaaaa-aaafa-cai
nns-ic-ckbtc-minter has no local canister ID.
```
Do I need to start DFX with a certain flag to get these?  I think ckBTC works that way.