The following events are related to the United States’ conflict with Iran over oil. Drag them into the order in which they occurred, with the earliest on top.

The price of gas in the United States skyrocketed.

Iran decided to stop the shipment of oil to the United States.

Iran went through national turmoil that involved the United States.

The United States invested in new sources of oil and created oil reserves.

To determine the correct chronological order of the events related to the United States' conflict with Iran over oil, we need to analyze the context and historical sequence. Here is the correct order, starting from the earliest event:

1. Iran went through national turmoil that involved the United States.
Explanation: This event refers to the Iranian Revolution of 1979, which led to the overthrow of the Shah and the establishment of an Islamic Republic. The United States had a significant role in these events, notably due to its previous support of the Shah.

2. Iran decided to stop the shipment of oil to the United States.
Explanation: Following the Islamic Revolution, Iran's new government (under Supreme Leader Ayatollah Khomeini) decided to suspend oil exports to the United States as a form of political retaliation.

3. The United States invested in new sources of oil and created oil reserves.
Explanation: In response to the oil shortage resulting from the Iranian oil halt, the United States undertook initiatives to reduce dependency on Iranian oil. This involved domestic investments in alternative sources of oil, such as offshore drilling and shale extraction methods, as well as the creation of strategic oil reserves for emergency situations.

4. The price of gas in the United States skyrocketed.
Explanation: As a consequence of the halted oil shipments from Iran and the subsequent turmoil in global oil markets during this period, the shortage of supply resulted in a sharp increase in gas prices within the United States.

Therefore, the correct chronological order of the events is:
1. Iran went through national turmoil that involved the United States.
2. Iran decided to stop the shipment of oil to the United States.
3. The United States invested in new sources of oil and created oil reserves.
4. The price of gas in the United States skyrocketed.

A. Warsaw Pact is formed

B. Korean War

C. ​Berlin Wall is Built

D. World War II Ends and the Cold War Begins

E. ​China Divides into Two Countries (People’s Republic of China and Taiwan)
F. Soviet Union Collapses (Establishment of the Russian Federation

G. Soviet Union signed friendship treaty with China
H. Fall of the Berlin Wall

I. Cuban Missile Crisis

J. North Atlantic Treaty Organization is formed

K. ​Vietnam War is over

L. ​Truman Doctrine announced to Congress

M. Germany is reunited

N. ​Mikhail Gorbachev​ and his advisers adopted "Glasnost"
O. ​The Great Leap Forward in China

P. Berlin Airlift Ends

Q. Winston Churchill delivers the Iron Curtain Speech

R. US is defeated and humiliated at the Bay of Pigs in Cuba
S. Vietnam War Begins