Trump's cash for troops plan has some logic, and big risks

Being a U.S. ally might soon get a lot more expensive. The Trump administration is reportedly preparing a plan that would force countries not only to pay for the full cost of hosting American troops in their territory, but also to pony up an additional 50% premium on that bill for the security that the U.S. soldiers provide.

By the numbers: Under those terms, some countries will pay as much as six times the amount they currently pay. To put this in perspective, U.S. troops are stationed in more than 100 countries around the world. There are 56,000 American soldiers in Japan, 35,000 in Germany, 28,500 in South Korea, 12,000 in Italy, and 9,000 in the U.K.

• The leak of this plan may merely be the opening bid in a series of tough negotiations, but let's take it at face value.

The argument for:

Those in Washington who favor this plan, led by Donald Trump, are asking a few simple questions:

• World War II ended almost 75 years ago, so why is the U.S. still responsible for guaranteeing the security of Germany and Japan, which are now among the richest countries on Earth?
• Haven't Germany and Japan become prosperous in part because U.S. protection allows them to avoid spending billions on their own defense?
• If U.S. troops and taxpayers must continue to accept this responsibility, shouldn't countries that benefit from the U.S. presence pay fully for the privilege?
• Are those who live in these countries and want U.S. troops leave prepared for their governments to take much more money from their paychecks while cutting their pensions and benefits to pay more for defense?

The argument against:

• The U.S. isn't simply doing other countries a favor by placing troops on their soil — those soldiers deliver geopolitical benefits that can't be measured in dollars and cents. U.S. bases in Japan, South Korea, Germany, and the Middle East make the U.S. a force to be reckoned with in all key regions of the world. Chip away at that, and others will try to fill the gap.
• Raise the cost to allies and watch how fast taxpayers in these countries push for the Americans to leave. You might not think that's in their interest, but many of them may well think otherwise.

• The U.S. benefits economically, politically, and militarily from stability in Asia, Europe, and the Middle East. That stability depends on the willingness of the only nation capable of projecting military power into every region to play a leadership role in keeping the peace.

The bottom line: If President Trump moves forward with this plan, the next important question might be equally simple: What happens if allies refuse to pay?

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