Houthi "Scud like" Missile kills scores of Saudi Troops.

via Press TV

A large number of Saudi soldiers have been killed in a Yemeni missile attack against a military base in Saudi Arabia’s southwestern border region of Asir.
An unnamed Yemeni military source said military forces and their allies launched a ballistic missile at the al-Montazah base in Asir on Tuesday, leaving scores of Saudi troopers and their mercenaries dead and injured, Arabic-language al-Masirah television network reported.
The source added that two Saudi armored vehicles were also destroyed in the attack.
Shortly afterward, Yemeni soldiers and fighters from the Popular Committees fired several artillery rounds at the Mosallas al-Rakbah base in the Saudi Jizan region, located 967 kilometers southwest of the capital, Riyadh.
A blaze swept through the military site as the projectiles struck.
Separately, Yemeni soldiers and allied fighters launched a domestically-manufactured Zelzal-2 (Earthquake-2) missile at a gathering of Saudi-sponsored militiamen loyal to the former government in the al-Maslub district of Yemen’s northern province of Jawf.
Several pro-Saudi gunmen also lost their lives and sustained injuries when their military camp was targeted by Yemeni forces in the al-Hariqiyah area of the southwestern province of Ta’izz.

Story here. 

I wonder if anyone has wargamed mass firing of tactical ballistic missiles against a high value target?  How would a battalion in the attack handle the added stress of facing precision ballistic missile fire?  I know a Marine Corps Task Force wouldn't be equipped/able to defend itself against such an attack but could a similar US Army formation?

There is a lesson here but I'm not sure what it is.  Is this a credible threat or a one off that's giving the Saudis fits?