For some supporters, England will be the easiest team to follow simply because they dominate the conversation.
That is what makes them such a divisive fallback. They are visible, familiar and likely to go deep. They are also the team many Irish supporters most enjoy resisting.
The host nation often becomes the easiest neutral watch. Full stadiums, a fast-moving tournament atmosphere and a sense of occasion usually pull in floating support.
They may not be everyone’s romantic choice, but they are a practical one.
If Irish fans want distance from the usual giants, Iran feels like the kind of team neutrals often adopt.
That may be the real answer here: not the biggest team, but the most interesting one.
Whatever Irish fans choose, the first few days of the tournament will decide plenty. A dramatic opener, a breakout player or an upset result can create an adopted team overnight - and once next Thursday arrives, that search for a World Cup story starts all over again.