France imports 0 oil directly through Hormuz, but when the Strait closes, all other countries start raising their safety stock which increases oil prices. This makes France's stockouts very expensive mostly due to price (not flows). Which is contagion without direct connection.

Think of the 2008 crisis where companies that had nothing to do with Credit Default Swaps were exposed to the crash due to network effects, potentially crashing the whole economy.

Then, the government intervened by bailing the banks out. Here, it's not really clear if there is even an effective intervention.