States are suing the federal government at a record pace, with Democratic attorneys general trying to block President Trump's policies on the environment, immigration, health care, marijuana and other issues. In addition, some states are defying federal authority by passing laws that counteract policies laid down in Washington. Tensions between the states and federal government are not new — states sued the administration of Democratic President Barack Obama dozens of times — but many governance experts say partisan hostility is at historically high levels. The friction has led to centuries-old questions about the division of power between federal and local authority and whether states have the right to reject policies created in Washington they believe are harmful or unconstitutional. Some states are so upset with what they see as federal budgetary excesses that they are calling for a constitutional convention to curb congressional spending authority. Meanwhile, partisan conflict between state legislatures and municipalities is also growing, with lawmakers sometimes blocking cities from enforcing local ordinances.