Can a soldier defend another soldier in xiangqi?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
Yes, but never diagonally. A soldier captures exactly the way it moves, forward and, after crossing, sideways. So it always defends the point straight ahead of it, and once it has crossed, the points beside it too. Two crossed soldiers side by side on the same rank defend each other, and a soldier directly behind another on the same file defends the one in front.
Why this differs from chess pawns
Chess pawns defend each other diagonally, which is the basis of a pawn chain. Xiangqi soldiers cannot, since they never capture diagonally at all, so there is no equivalent structure. Soldiers spread out from the start specifically because they are not meant to lean on each other the way pawns do; see how the soldier moves for the full picture.
When mutual defence actually happens
It comes up mainly in an advanced pawn storm near the enemy palace, where two or three crossed soldiers sitting on the same rank can hold each other up against a defender trying to pick them off one at a time.
Related questions
Can an uncrossed soldier be defended by anything?
Yes, by a chariot, horse or cannon, or by an elephant when it stands on one of the elephant's riverbank points, but not by another soldier, and not by the general, which never leaves its palace.
Is a defended soldier worth more than an undefended one?
In practice yes, since it cannot simply be picked up for free, though its nominal value does not change.
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