[salviati]

This would also add the requirement of an accurate internal clock.

[throwaway89201]

In theory, you can add some more complexity/fragility and have 'time notaries' sign the current time together with a challenge from the passport, verifiable against embedded public keys.

[Scoundreller]

Driveby bricking of passports, coming to an airport near you!

[namibj]

German id cards essentially record the newest issuance timestamp seen; then they block certificates that expired prior to this recorded value.