The Globe and Mail reports in its Wednesday, Jan. 28, edition that Bank of America strategist Michael Hartnett advised clients to short Canadian banks and buy United States banks with the proceeds as one of his top 15 trade ideas for 2015. The Globe's Scott Barlow writes that the trade is working extremely well in large part because of the weakness of the loonie. Recent information suggests it might start working even better in the months ahead. Mr. Hartnett's pessimism on Canadian banks is based on oil prices and the condition of the real estate markets on both sides of the border. He believes that weaker crude prices will have a larger negative effect on the Canadian economy than in the U.S. Also, Canadian bank lending related to real estate will slow while U.S. loans to home buyers and commercial real estate investors will accelerate. New home sales in the U.S. in December saw an 11.6-per-cent month-over-month gain in sales, the strongest set of December results since 2007. This was above expectations of a 2.7-per-cent increase and a clear sign of strength in the U.S. housing market. So far, Mr. Hartnett's trade idea has worked well but solely because of currency.