Because in the US, money has nowhere else to go. Stocks? Wildly overpriced. Real estate? Wildly overpriced. Bonds? Zero returns. Mineral extraction? Risky outlook. Energy sector? Subsidies are likely on the horizon, better to wait. Infrastructure? NIMBYs
That's not the case for the EU. Money gets reasonable returns in energy sector, industry, any investment in Eastern Europe, tourism, PPP infrastructure projects, etc.