Why did Emperor Wu of the Han Dynasty want Zhang Qian to go to the Western Regions?

Neither of the above answers is accurate enough. At that time, Emperor Wu of the Han Dynasty sent Zhang Qian to the Western Regions in order to contact other countries to attack the Huns, but the contact was with Yue, not Dawan. Because the Yue kingdom was attacked by the Huns, not only the king was killed, but the whole Yue kingdom was forced to move to avoid the Huns. It can be said that there is a blood feud between Yueshi Kingdom and Xiongnu.

But at that time, Empress Yue did not agree with Zhang Qian, but traded goods with the Han Dynasty. Objectively, Zhang Qian's mission to the Western Regions strengthened the trade and cultural exchanges between the Han Dynasty and the Western Regions.