By Joseph Krauss And Jon Gambrell Iran has spent decades building multi-tiered military capabilities at home and across the region that were at least partly aimed at deterring the United States from attacking it. By entering Israel’s war, the U.S. may have removed the last rationale for holding them in reserve. That could mean a wave of attacks on U.S. forces in the Middle East, an attempt to close a key bottleneck for global oil supplies or a dash to develop a nuclear weapon with what remains of Iran’s disputed program after American strikes on three key sites. A decision to retaliate against the U.S. and its regional allies would give Iran a far larger target bank and one that is much closer than Israel, allowing it to potentially use…