The United States is stepping up the face-to-face military advice it provides to Ukraine, dispatching a three-star general to Kyiv to spend considerable time on the ground. The Americans are pushing for a conservative strategy that focuses on holding the territory Ukraine has, digging in and building up supplies and forces over the course of the year. The United States has given vast military and economic support to Ukraine, more than $111 billion over the past two years. But a significant number of Republicans now say they oppose further spending, and others are demanding to see a new strategy before...