There is much in our government that doesn't seem to work as effectively as it should. So it is ironic that some have trained their fire on a government agency that works well: the Export-Import Bank.

Ex-Im's mission is to ensure that U.S. companies — large and small — have access to the financing they need to sell their goods and services to customers all over the world. Ex-Im does not compete with the private sector. It fills gaps in trade finance by working with financial institutions to ensure that U.S. businesses operate on a level playing field as they compete for international business.

Ex-Im's opponents — including the Competitive Enterprise Institute's Ryan Young, who argued for the closure of the bank in these pages on Aug. 8 — say that Ex-Im affords certain industries and firms an unfair advantage and exposes taxpayers to unnecessary risk. In fact, Ex-Im returns a profit to taxpayers and enhances fairness for American businesses as they compete in markets outside our borders. Without it, American-made goods could very likely be undercut in countries where export credit agencies are active.

Export credit agencies are recognized throughout the world as an important source of trade finance that supports domestic jobs. Sixty official export credit agencies have poured more than $1 trillion into trade finance in recent years, reducing the cost of their countries' products for buyers in other nations, according to the Organization for Economic Cooperation and Development. Moreover, a study by the Asian Development Bank concluded that a 5% increase in access to trade finance leads to a 2% increase in production and jobs.

American companies need access to the nearly 95% of global consumers who live outside the U.S. so that they can grow, thus creating jobs. Abandoning Ex-Im would make it unnecessarily harder for American companies to achieve this goal.

Moreover, Ex-Im hardly poses a risk to taxpayers: it has paid $2 billion in profit to the U.S. Treasury in the last five years. The loans that Ex-Im guarantees are subject to the same types of strict risk analysis performed by private-sector lenders. They are backed by underlying commercial trade transactions, which in the first quarter of 2014 had a historically low active-default rate of 0.211 percent—more than four times lower than first mortgages during the same period.

Ex-Im's detractors label its activities "corporate welfare," arguing that a few large corporations monopolize resources made possible by taxpayer guarantees. However, in fiscal year 2013, Ex-Im financed a record 3,413 small business authorizations — nearly 90% of its total transactions. Ex-Im helped these small businesses compete against foreign firms without an unfair disadvantage.

It is true that iconic American companies such as Boeing and General Electric account for a significant chunk of Ex-Im's total dollar financing. Tens of thousands of high-tech and manufacturing jobs across the country are sustained through the international business that results from these transactions. And the jobs are not only with Boeing and GE, but with hundreds of small- and medium-sized vendors, subcontractors and service providers.

If the Ex-Im charter is not renewed by September, there will be real economic ramifications. Dismantling this productive government agency will hurt the 1.2 million U.S. jobs supported by the bank and damage the credibility of the U.S. abroad. The arguments against Ex-Im don't square with the facts. The case for keeping it is rooted in good common sense.

Tod Burwell is president and chief executive of BAFT, the international transaction banking association.