Colombia also experienced major changes to its military and society, due to increased influence from the United States, but it was also able to maintain its sovereignty throughout the war, as well as avoid sending troops into battle.

Secondly, Colombia's imports were also dramatically affected, and again the United States was the sole source of many goods, such as rayon yarn, steel, machinery, graphite, and lead.

The OPA relented, and agreed to raise prices immediately and to adjust them in the future based on increased production and transportation costs.

Colombia was the only source of platinum for the German and Japanese war industries, and the United States moved quickly to buy out the entire supply through the Metals Reserve Company, which was an agency of the Reconstruction Finance Corporation.

Since the United States also needed additional supplies of platinum for its war effort, it assisted Colombia with technical advice on increasing production through the Foreign Economic Administration.

[1] At the beginning of the war, Colombia was home to a German colony - estimated by the United States government in December 1941 to consist of about 4,000 people - and a small village of Japanese farmers in Cauca.

The Americans were concerned about the possibility of a "fifth column" of subversives forming in Colombia and carrying out sabotage and the like against the nearby Panama Canal Zone.

The benefits of American economic assistance, and threats to cut it off, were irresistible, however, and as a result, Colombia monitored, interned, or deported hundreds of people from Germany, Japan, and Italy, during the war.

[1] The Black List After the Attack on Pearl harbor, the government of Colombia expressed strong support for the United States.

As a result, Japanese, German, and Italian property was confiscated, internment camps were established, and laws were emplaced to deter Axis espionage.

SCADTA was founded in 1919 by three German settlers and five Colombians, and by World War II was an important part of the transportation network of Colombia.

In 1931, after the American-owned Pan American World Airways acquired a controlling interest in SCADTA, it was discovered that many of the airline's pilots, technicians, and key administrators were German or Austrian, even though most had lived in Colombia for several years.

The United States was afraid that the SCADTA pilots were engaged in espionage, and could be plotting to convert civilian aircraft into bombers, in order to attack the Panama Canal.

However, in order to comply with the United States, Colombia passed laws requiring airlines to hire more Colombian citizens, and for 51% of the stock of these companies to be Colombian-held.

However, the Swiss aviation equipment was expensive and obsolete by 1939, and the Colombian government recognized the possibility that the British would most likely not be able to continue their naval assistance due to their own defense needs.

[1] Other points of the agreement included the exchange of technical advisers, cooperation on coastal patrols, and the aerial photographing of strategic areas within Colombia.

Colombia also made it clear that, although it was fully supportive of the fight against the Axis, it would do everything possible to limit the amount of American military activity taking place on or from its territory.

A 110-ton schooner, the Roamar belonged to a Colombian diplomat, and her sinking off San Andres by U-505 on July 21, 1942, gave Colombia the political grounds to declare war on Germany.

U-505's engineer, Hans Goebeler, said the following about the incident: "We couldn't leave the evidence [of attacking a neutral ship] floating around, so we sank her with the deck gun."

The Germans were completely surprised by the sudden appearance of the enemy destroyer, so they were unable to get their deck gun into action in time, and instead had to dive to prevent being hit by Colombian gunfire.

[11] According to the Colombian Navy's report of the incident, the men aboard Caldas struck the U-boat twice with 105-mm gunfire before it dived, and then finished it off with depth charges.

Ultimately, U-154 met her end off Madeira, on July 3, 1944, when she was sunk with all hands lost by the American destroyer escorts USS Inch and Frost.

After Pumarejo's first term in 1934-1938, President Eduardo Santos succeeded him and developed a policy of protection for the national industry as an economic measure to resist the effects caused by the Second World War.

Despite this, the demand for consumer goods increased around the world when the war ended which helped stimulate the Colombian economy by the large export of coffee and bananas.

Soon after, the Conservative Party gained control of the government in 1946 which eventually resulted in a large period of civil unrest known as "La Violencia.

The creation of the Fuerza Aérea Colombiana (Colombian Airforce) was established officially in December 1944 however the separation between aviation and army had started to take place in 1942.