It would only need to be allowed into LA&#x2F;Long Beach and Shanghai to be profitable.  And it would probably be allowed in those ports, even if it were emitting a bright Cherenkov glow while underway.<p>In fact, on the list of busiest ports by container volume, Rotterdam, at #11, is the first I might be worried about, and then Hamburg and Antwerp, at #15 and #16.<p>With the size of cargo container ships built nowadays, the additional engineering requirements of a full-blown built-in nuclear reactor is more than justified.  Even retrofitting the largest bunker-burning ships might be justified.