1- A Hag in a dream will have the same meaning as a banner - that is, a standard or a place round which people with common aims and beliefs can gather. It may represent old-fashioned principles and beliefs.
2- The national Hag will signify a degree of patriotism which may be necessary; or possibly the need to be more militant.
3- Spiritual crusades often require standards of behaviour.... Ten Thousand Dream Dictionary
Psychological / emotional perspective: Any national flag will signify a degree of patriotism that may be necessary, or possibly the need to be more militant. Now with its connection to international sport, a flag can suggest an opportunity for exhibitionism.... Dream Meanings of Versatile