@rogercooper I want to post my complete solution as it has some tricks people might want to use. I was surprised that you can use both a cartesian join "^" and a standard join ":" in the same foreach structure.
Another neat trick is that you can use Export/Export game.xml file to resolve all the for eaches. Useful if you want to check that the result is correct or if you need to customize some entries.
<variableList>
<variable name="MajorPower">
<element name="Britain"/>
<element name="Soviet_Union"/>
<element name="United_States"/>
<element name="Western_Europe"/>
</variable>
<variable name="NeutralArea">
<element name="Afghanistan"/>
<element name="Borneo/Celebes"/>
<element name="Ethiopia"/>
<element name="Finland"/>
<element name="Iran"/>
<element name="Ireland"/>
<element name="Java"/>
<element name="Rio de Oro"/>
<element name="Spain"/>
<element name="Sumatra"/>
<element name="Sweden"/>
<element name="Switzerland"/>
<element name="Thailand"/>
<element name="Tibet"/>
</variable>
<variable name="NeutralSetup">
<element name="infantry"/>
<element name="infantry"/>
<element name="infantry:infantry"/>
<element name="infantry:infantry:infantry"/>
<element name="infantry:armor:fighter"/>
<element name="infantry"/>
<element name="infantry"/>
<element name="infantry"/>
<element name="infantry:infantry:infantry:infantry:armor:fighter"/>
<element name="infantry"/>
<element name="infantry:infantry:infantry:armor:fighter"/>
<element name="infantry:infantry:infantry:fighter"/>
<element name="infantry:infantry"/>
<element name="infantry:infantry"/>
</variable>
</variableList>
and
<attachment name="conditionAttachmentEveryTurn" attachTo="United_States" javaClass="games.strategy.triplea.attachments.RulesAttachment" type="player">
<option name="rounds" value="1-100"/>
</attachment>
<attachment foreach="$NeutralArea$" name="conditionAttachment@NeutralArea@Non_Aligned" attachTo="Non_Aligned" javaClass="games.strategy.triplea.attachments.RulesAttachment" type="player">
<option name="directOwnershipTerritories" value="@NeutralArea@" count="1"/>
</attachment>
<attachment foreach="$NeutralArea$" name="triggerAttachment@NeutralArea@RemoveUnits" attachTo="Non_Aligned" javaClass="games.strategy.triplea.attachments.TriggerAttachment" type="player">
<option name="players" value="Non_Aligned"/>
<option name="uses" value="1"/>
<option name="removeUnits" value="@NeutralArea@:All" count="5"/>
</attachment>
<attachment foreach="$MajorPower$^$NeutralArea$:$NeutralSetup$" name="triggerAttachment@MajorPower@@NeutralArea@" attachTo="@MajorPower@" javaClass="games.strategy.triplea.attachments.TriggerAttachment" type="player">
<option name="conditions" value="conditionAttachmentEveryTurn"/>
<option name="conditions" value="conditionAttachment@NeutralArea@Non_Aligned"/>
<option name="players" value="@MajorPower@"/>
<option name="chance" value="1:80"/>
<option name="chanceIncrementOnFailure" value="1"/>
<option name="when" value="before:@MajorPower@Purchase"/>
<option name="placement" value="@NeutralArea@:@NeutralSetup@" />
<option name="changeOwnership" value="@NeutralArea@:Non_Aligned:@MajorPower@:false"/>
<option name="activateTrigger" value="triggerAttachment@NeutralArea@RemoveUnits:1:false:false:false:false"/>
<option name="uses" value="1"/>
</attachment>
