If Thomas Jefferson could catch up on today's political news, he'd find the brouhaha hauntingly familiar. Jefferson's critics claimed that his purchase of the Louisiana territory was unconstitutional and rebelled against the decision to grant citizenship to thousands of non-English speaking residents. For that matter, the $15 million pricetag -- the equivalent of $500 million today -- seemed insanely steep. Nowadays, it's clear that the opposite was true: The sale worked out to something like $0.42 per acre.
America doesn't buy presents only for itself: almost 150 years later, it finished World War II by buying a gift for Europe: the Marshall Plan. Surprisingly, the proposal to fund the rebuilding of Europe enjoyed strong bipartisan support in Congress, in spite of its huge price tag. In 1948, it cost $17.6 billion, the equivalent of $168 billion today. Even so, it was probably a bargain in the long run -- and, like buying a friend a new Playstation, it's a gift we got to enjoy, too. In this case, our present bought us good relations with most of Western Europe and laid the groundwork for 64 years (and counting) of peace in the region.
Of course, shortly before America purchased the Marshall Plan, it had also bought itself a huge gift: nuclear deterrence. The Manhattan Project, a $20 billion ($282 billion in today's dollars) push to create the nuclear bomb, arguably brought a quicker end to World War II and established the U.S. as a dominant force in the postwar world.
Then again, it was only a few years before the Soviet Union detonated its own nuclear bomb, launching the Cold War. Over the course of the 44-year ideological struggle, the U.S. and the U.S.S.R. never directly met on a battlefield, but rather fought each other through extremely expensive (and ideologically uncomfortable) alliances that managed to destabilize much of Asia, South America and Africa. It was also really expensive: all told, we spent an estimated $7.5 trillion on the Cold War, making it arguably the costliest thing that the U.S. has ever financed.
While the Cold War was pricey and destructive, it also had its high points. Launched partially in response to the USSR's Sputnik satellites, America's space program started as an outgrowth of the military, but soon transformed into one of the country's grandest national efforts. At $25.4 billion ($159 billion today), the Apollo moon landings weren't cheap, but they still stand as a high point in U.S. -- and human -- history.
Back on Earth, America was also building the Eisenhower Interstate System. Constructed between 1956 and 1991, the 47,182-mile network has been described as "the largest public works program since the pyramids." Of course, it hasn't been cheap, carrying an estimated price tag of $484 billion -- and counting. Then again, it has generated an estimated $6 in economic activity for every $1 it has cost.
Not all of America's gifts have been quite so productive. The Wall Street bailout, which involved a $4.76 trillion disbursement, of which $1.54 trillion is still outstanding, ranks right below the Cold War in terms of biggest government expenditures.