I agree with the poster on page 3. A combined force of 400 vehicles is way too small to even consider an invasion. Now if you had a tank division along with an Infantry division with necessary air cover and helicopter support we may have something. This a really a small force based on those pics and the reports. While our technology is a great force multiplier, there is no way any general would invade a country with such a small force. Now, if they are there to defend Jordan, or provide a "speed bump" against an invading force until reinforcements arrive then that would make some sense.

A joint military drill makes the most sense based on the info in the OP.