All jurisdictions which follow British law, or which are based on British law to some extent (like the U.S.) have judicial ethical guidelines that generally req

All jurisdictions which follow British law, or which are based on British law to some extent (like the U.S.) have judicial ethical guidelines that generally require a judge to stand down if he makes statements that indicate or suggest he cannot impartially judge the case before him based on the law or merits that specifically apply. This judge said "The US is the enemy" while presiding over a case in which the U.S. was the primary opposing litigant. A statement that strongly worded strongly suggests he would not be able to impartially judge the remaining proceedings. Consequently, the instant he made that statement, he was ethically obligated to stand down. In some jurisdictions, not standing down would result in disrobement and potentially disbarrment. Indeed, in most jurisdictions with these rules, judicial decisions can be struck down for a judge's refusal to stand down after making such statements. The one exception is SCOTUS, because its decisions are not subject to further review except by SCOTUS itself.