The US let the Russians break themselves fighting the Eastern front while they invaded north Africa. The North African front was basically secure while Stalingrad was happening, and if the US applied more pressure to Germany in this period, as the Russian requested, the Germans probably would not have done so much population damage to Russia.

Bitterness of this fueled a lot of ideological tensions. I was also taught that a large motivation of dropping the Bomb was to scare the Russians.

Source: My Highschool education. Obviously, commentary on WWII is not objective, but I stand by my thesis, considering the actual action that the United States engages in in present times. Its in our history to be both ideologically driven and meta gamers.

It’s hard to imagine the scale of the U.S. air operations against Germany and say the U.S. let the Russians break themselves without doing anything to help. Or look at the disaster that was Market Garden and think the U.S. could have invaded earlier. The U.S. was under no ethical obligation to throw away lives uselessly in a German blender as a distraction.

Without Lend Lease keeping the Russians supplied with food/logistics they would have starved and collapsed.

That line of argument doesn't make any sense to me. The Americans were actually in FAVOR of a cross-channel invasion in 1942-43 (see operation sledgehammer and operation roundup), but were shouted down by the British. Which, to their credit, was fair: the Allies lacked the ability to launch a large amphibious assault in 1942 into France. They lacked a sufficient fleet of landing craft, along with the proper doctrine, the same degree of air superiority they would have in 1944.

"The North African front was basically secure while Stalingrad was happening"

That doesn't make any sense. Operation Torch (the Allied invasion of Morocco and Algeria) didn't even start until Nov 8th, and Montgomery's position in Libya was hardly "secure" before November. But the Soviets were already launching counter-offensives and encircling the German army by the end of November. If you're counting from the beginning of the main Stalingrad offensives, August 1942, yeah maybe you could call the North African theater "stable", if by stable you mean that the Allies just one a defensive victory and managed to stall out an offensive into Egypt. But it's not like they could cancel their planned invasion of Algeria and Morocco and re-plan for an invasion of France in a couple months.

Plus the US would be invading mainland Europe Sept 3rd of 1943, and I really don't think they could have performed a successful invasion anytime sooner.