buffnut453
Captain
Bolster Latvia, Lithuania and Estonia's defenses and use them as a supply corridor.
Not really an option. The following is from Wiki (yes...I know) but it gives a gist of the problems the three tiny Baltic nations faced in 1939. The focus is Latvia but the others were little different:
Early in the morning of 24 August 1939, the Soviet Union and Nazi Germany signed a 10-year non-aggression pact, called the Molotov–Ribbentrop Pact.[52] The pact contained a secret protocol, revealed only after Germany's defeat in 1945, according to which the states of Northern and Eastern Europe were divided into German and Soviet "spheres of influence".[53] In the north, Latvia, Finland and Estonia were assigned to the Soviet sphere.[53] A week later, on 1 September 1939, Germany invaded Poland; on 17 September, the Soviet Union invaded Poland as well.[54]: 32
After the conclusion of the Molotov-Ribbentrop Pact, most of the Baltic Germans left Latvia by agreement between Ulmanis's government and Nazi Germany under the Heim ins Reich programme.[55] In total 50,000 Baltic Germans left by the deadline of December 1939, with 1,600 remaining to conclude business and 13,000 choosing to remain in Latvia.[55] Most of those who remained left for Germany in summer 1940, when a second resettlement scheme was agreed.[56] The racially approved being resettled mainly in Poland, being given land and businesses in exchange for the money they had received from the sale of their previous assets.[54]: 46
On 5 October 1939, Latvia was forced to accept a "mutual assistance" pact with the Soviet Union, granting the Soviets the right to station between 25,000 and 30,000 troops on Latvian territory.[57] State administrators were murdered and replaced by Soviet cadres.[58] Elections were held with single pro-Soviet candidates listed for many positions. The resulting people's assembly immediately requested admission into the USSR, which the Soviet Union granted.[58] Latvia, then a puppet government, was headed by Augusts Kirhenšteins.[59] The Soviet Union incorporated Latvia on 5 August 1940, as the Latvian Soviet Socialist Republic.
The 5 Oct 39 "mutual assistance pact" doesn't give a lot of time for Latvia to be a funnel for arms to Poland...and it's a route that could easily be closed given the distance of any Allies from the Baltic nations.
One other thing that leapt out at me from the Wiki page was the rather chilling part of the Molotov-Ribbentrop Pact about respective "spheres of influence" for Nazi Germany and the USSR. We're hearing that EXACT term being used by Moscow to rationalize its actions today in Ukraine....because the west is impinging on what Moscow sees as its rightful area of hegemony. We truly are seeing efforts to replay WW2 and resurrect the USSR.