What are the2 largest deserts on the arabian peninsula?

The biggest Desert in the Arabian Peninsula is the Arabian Desert - it take up the majority of the Peninsula.

The second largest desert in the Arabian Peninsula is called Rub' al Khali (meaning : "empty quarter")- it is also the biggest sand desert in the world.
 

It is the doctrine that the us had the right and duty to expand throughout north america. it just means they believed they had the right to expand westward and they did! they stated with the 13 colonies and then they kept moving gaining different territories throughout the years

Magma is outside the volcano  and lava is inside the volcano.