Opinion of the Court. 322 U.S. thereto the value of the machinery in question, fixed at $618,000. This included property acquired from other tool manufacturers as above described, $444,000; that manufactured by Mesta, $14,000; lathes brought from the Watervliet Arsenal, $160,000. Mesta protested and exhausted administrative remedies without avail, and on July 30, 1942, paid under protest $5,137.12, the amount of the tax attributable to this increased assessment. Mesta took a timely appeal allowed by statute to the Court of Common Pleas. The United States petitioned to intervene, reciting that it would be required to reimburse Mesta by force of its contract. Intervention was permitted against objection by the County, and the United States has participated in the litigation since. Mesta attacked the assessment under both state and federal law, claiming that under the State Tax Law property belonging to another was not to be considered a part of its mill and that if construed to authorize assessment and taxation of this machinery, the statute violated the Federal Constitution. The Court of Common Pleas held that the State Act authorized the assessment, but that the machinery here involved was "owned by the United States" and so for constitutional reasons could not be included. The Supreme Court of Pennsylvania, on appeal of the County, reversed, and reinstated the assessment. It held that under the state law regardless of who held the title to it the machinery constituted a part of the mill for purposes of assessment and was properly assessed as real estate. It acknowledged that property held by the United States is "beyond the pale of taxation" by a state, but this assessment, it said, is not against the United States but against Mesta, which is operating its mill for private purposes. If Mesta defaulted in tax payments, the Court held that "the paramount rights of the Government in the 174 Opinion of the Court. machinery could not be divested or in any way affected," hence the Government could suffer no loss. Evidence that the machinery was not owned by Mesta it held to be irrelevant and improperly admitted. Two Justices dissented. The United States and Mesta appealed and we postponed consideration of jurisdictional questions to the hearing on the merits. I. It is denied that the Government has valid title to the machinery. This contention is urged by the member cities of the National Institute of Municipal Law Officers, permitted to file a brief and to argue orally as amici curiae. Their position is that "the Government is subject to the legal rules applicable to private transactions." Under Pennsylvania law transfer of title to personal property to be good as against subsequent purchasers and lienors must be accompanied by delivery of possession. They say that inspection and acceptance by a contracting officer on behalf of the United States at the Mesta plant did not under decisional law of Pennsylvania amount to delivery of possession to the United States and hence that its title is defective. The position of the County is less extreme. It argued earlier in the litigation that the machinery became part of Mesta's real estate upon installation and that the United States had only "a reversionary interest after the termination of the contract." It later conceded that title to the property was not in Mesta "except for tax purposes.' The Pennsylvania Supreme Court thought it immaterial whether title was in the Government, but said, “. . . this private arrangement between the Mesta Company, the owner of the land and buildings and operator of the mill, and the federal government, the owner of the machinery, which treats the equipment as personal property and per Opinion of the Court. 322 U.S. mits the latter to remove it at the termination of the contract, can in no way change the legal effect of the Act of Assembly which specifically designates machinery, under these circumstances, as real estate for tax purposes.' We do not determine whether, under Pennsylvania law, the retention of possession by Mesta would protect only good-faith purchasers or lienors who relied upon it or whether, as urged by the amici, it also makes the Government's title imperfect as against these taxing authorities, who were fully advised of the Government's claim before the assessment was made. Even if the latter were true, we do not think the state law would be decisive of the question of title. The Constitution provides that "The Congress shall have Power to dispose of and make all needful Rules and Regulations respecting the Territory or other Property belonging to the United States. ." Art. IV, § 3, cl. 2. It also gives Congress the power "To make all Laws which shall be necessary and proper for carrying into Execution" all powers vested in the Government or in any department or officer thereof, Art. 1, § 8, cl. 18, and it makes the laws of the United States enacted pursuant thereto "the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding." Art. VI, cl. 2. Every acquisition, holding, or disposition of property by the Federal Government depends upon proper exercise of a constitutional grant of power. In this case no contention is made that the contract with Mesta is not fully authorized by the congressional power to raise and support armies and by adequate congressional authorization to the contracting officers of the War Department. It must be accepted as an act of the Federal Government warranted by the Constitution and regular under statute. 174 Opinion of the Court. Procurement policies so settled under federal authority may not be defeated or limited by state law. The purpose of the supremacy clause was to avoid the introduction of disparities, confusions and conflicts which would follow if the Government's general authority were subject to local controls. The validity and construction of contracts through which the United States is exercising its constitutional functions, their consequences on the rights and obligations of the parties, the titles or liens which they create or permit, all present questions of federal law not controlled by the law of any State. Clearfield Trust Co. v. United States, 318 U. S. 363; Jackson County v. United States, 308 U. S. 343; Carpenter v. Shaw, 280 U. S. 363; Utah Power & Light Co. v. United States, 243 U. S. 389; United States v. Ansonia Brass & Copper Co., 218 U. S. 452; see D'Oench, Duhme & Co. v. Federal Deposit Ins. Corp., 315 U. S. 447; Deitrick v. Greaney, 309 U. S. 190; Federal Land Bank v. Bismarck Lumber Co., 314 U. S. 95. Federal statutes may declare liens in favor of the Government and establish their priority over subsequent purchasers or lienors irrespective of state recording acts. Detroit Bank v. United States, 317 U. S. 329; United States v. Snyder, 149 U. S. 210. Or the Government may avail itself, as any other lienor, of state recording facilities, in which case, while it has never been denied that it must pay nondiscriminatory fees for their use, the recording may not be made the occasion for taxing the Government's property. Federal Land Bank v. Crosland, 261 U. S. 374; Pittman v. Home Owners' Loan Corp., 308 U. S. 21. We hold that title to the property in question is in the United States and is effective for tax purposes. II. The County denies, however, that it is taxing property belonging to the United States. First, it says it taxes only the land, which the United States does not own; and the Opinion of the Court. 322 U.S. machinery is not taxed, but is considered only as an enhancement of the value of the land to Mesta, its owner. Secondly, it says the lien of the tax does not encumber and the process of collection does not involve any sale or other interference with the machinery. The Pennsylvania Supreme Court has upheld the questioned tax because upon these grounds it concluded that no interference with the federal function resulted. "Where a federal right is concerned we are not bound by the characterization given to a state tax by state courts or legislatures, or relieved by it from the duty of considering the real nature of the tax and its effect upon the federal right asserted." Carpenter v. Shaw, 280 U. S. 363, 367-68. It is not contended that the scheme of taxation employed by Pennsylvania is anything other than the old and widely used ad valorem general property tax. This taxation plan involves the identification and valuation of the variable individual holdings to be taxed, commonly called the assessment, the application of a uniform rate calculated on the need for public revenues, and the collection, in default of payment, by distraint and sale of the property assessed and taxed. This form of taxation is not regarded primarily as a form of personal taxation but rather as a tax against the property as a thing. Its procedures are more nearly analogous to procedures in rem than to those in personam. While personal liability for the tax may be and sometimes is imposed, the power to tax is predicated upon jurisdiction of the property, not upon jurisdiction of the person of the owner, which often is lacking without impairment of the power to tax. In both theory and practice the property is the subject of the tax and stands as security for its payment. The Pennsylvania statutes embody this scheme of taxation. They are a century old. The basic provision reads: |